TY  - JOUR
AU  - Pjević, Dejan J.
AU  - Savić, Tatjana D.
AU  - Petrović, Suzana
AU  - Peruško, Davor
AU  - Čomor, Mirjana
AU  - Kovač, Janez
PY  - 2021
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/9841
AB  - The influence of deposition and annealing parameters on optical, structural and photocatalytic properties of N-doped titanium-dioxide (TiO2) thin films have been studied. Anatase and anatase-rutile crystalline phase mixture TiO2 thin films were obtained depending on the reactive direct current (DC) sputtering and annealing conditions. Deposition in the nitrogen atmosphere produced N-doped TiO2 thin films with energy gap values shifted towards visible region in comparison with thin TiO2 films deposited without nitrogen in the atmosphere. The role of substitutional and interstitial nitrogen atoms incorporated in obtained crystalline structures during the deposition was shown important and was reflected in the efficiency of photocatalysis. It was found that thin TiO2 films with more substitutional incorporated nitrogen exhibits better photocatalytic properties. These results could be of importance towards achieving controlled synthesis of N-doped TiO2 thin films with desired structural and optical properties, especially with improved photo-activity in the visible part of the solar spectrum.
T2  - ECS Journal of Solid State Science and Technology
T1  - Influence of Nitrogen Incorporation Sites on Structural and Optical Properties of Sputtered TiO2-N Thin Films with Improved Visible Light Activity
VL  - 10
IS  - 5
SP  - 053002
DO  - 10.1149/2162-8777/abffb2
ER  - 

@article{
author = "Pjević, Dejan J. and Savić, Tatjana D. and Petrović, Suzana and Peruško, Davor and Čomor, Mirjana and Kovač, Janez",
year = "2021",
abstract = "The influence of deposition and annealing parameters on optical, structural and photocatalytic properties of N-doped titanium-dioxide (TiO2) thin films have been studied. Anatase and anatase-rutile crystalline phase mixture TiO2 thin films were obtained depending on the reactive direct current (DC) sputtering and annealing conditions. Deposition in the nitrogen atmosphere produced N-doped TiO2 thin films with energy gap values shifted towards visible region in comparison with thin TiO2 films deposited without nitrogen in the atmosphere. The role of substitutional and interstitial nitrogen atoms incorporated in obtained crystalline structures during the deposition was shown important and was reflected in the efficiency of photocatalysis. It was found that thin TiO2 films with more substitutional incorporated nitrogen exhibits better photocatalytic properties. These results could be of importance towards achieving controlled synthesis of N-doped TiO2 thin films with desired structural and optical properties, especially with improved photo-activity in the visible part of the solar spectrum.",
journal = "ECS Journal of Solid State Science and Technology",
title = "Influence of Nitrogen Incorporation Sites on Structural and Optical Properties of Sputtered TiO2-N Thin Films with Improved Visible Light Activity",
volume = "10",
number = "5",
pages = "053002",
doi = "10.1149/2162-8777/abffb2"
}

Pjević, D. J., Savić, T. D., Petrović, S., Peruško, D., Čomor, M.,& Kovač, J.. (2021). Influence of Nitrogen Incorporation Sites on Structural and Optical Properties of Sputtered TiO2-N Thin Films with Improved Visible Light Activity. in ECS Journal of Solid State Science and Technology, 10(5), 053002.
https://doi.org/10.1149/2162-8777/abffb2

Pjević DJ, Savić TD, Petrović S, Peruško D, Čomor M, Kovač J. Influence of Nitrogen Incorporation Sites on Structural and Optical Properties of Sputtered TiO2-N Thin Films with Improved Visible Light Activity. in ECS Journal of Solid State Science and Technology. 2021;10(5):053002.
doi:10.1149/2162-8777/abffb2 .

Pjević, Dejan J., Savić, Tatjana D., Petrović, Suzana, Peruško, Davor, Čomor, Mirjana, Kovač, Janez, "Influence of Nitrogen Incorporation Sites on Structural and Optical Properties of Sputtered TiO2-N Thin Films with Improved Visible Light Activity" in ECS Journal of Solid State Science and Technology, 10, no. 5 (2021):053002,
https://doi.org/10.1149/2162-8777/abffb2 . .

TY  - JOUR
AU  - Savić, Tatjana D.
AU  - Carević, Milica
AU  - Mitrić, Miodrag
AU  - Kuljanin-Jakovljević, Jadranka Ž.
AU  - Abazović, Nadica
AU  - Čomor, Mirjana
PY  - 2020
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/8617
AB  - Hexagonal ZnIn2S4 is synthesized by simple and low-cost hydrothermal route. TEM images revealed formation of nanosheets. The estimated band-gap energy of synthesized sample is in the visible spectral region and has a value of about 2.25 eV. Photocatalytic properties of synthesized sample are probed in photocatalytic degradation of three selected dyes different in nature and structure, Rhodamine B (RhB), Methylene blue (MB) and Methyl orange (MO), under the illumination with simulated Solar light. Obtained results revealed that photocatalytic degradation of RhB and MO is mainly result of synergic effect of photogenerated holes and oxygen, while primary effect in ZnIn2S4/MB system is bleaching of the dye, but no photodegradation was observed. © 2019 Elsevier B.V.
T2  - Journal of Photochemistry and Photobiology A: Chemistry
T1  - Simulated solar light driven performance of nanosized ZnIn2S4/dye system: decolourization vs. photodegradation
VL  - 388
SP  - 112154
DO  - 10.1016/j.jphotochem.2019.112154
ER  - 

@article{
author = "Savić, Tatjana D. and Carević, Milica and Mitrić, Miodrag and Kuljanin-Jakovljević, Jadranka Ž. and Abazović, Nadica and Čomor, Mirjana",
year = "2020",
abstract = "Hexagonal ZnIn2S4 is synthesized by simple and low-cost hydrothermal route. TEM images revealed formation of nanosheets. The estimated band-gap energy of synthesized sample is in the visible spectral region and has a value of about 2.25 eV. Photocatalytic properties of synthesized sample are probed in photocatalytic degradation of three selected dyes different in nature and structure, Rhodamine B (RhB), Methylene blue (MB) and Methyl orange (MO), under the illumination with simulated Solar light. Obtained results revealed that photocatalytic degradation of RhB and MO is mainly result of synergic effect of photogenerated holes and oxygen, while primary effect in ZnIn2S4/MB system is bleaching of the dye, but no photodegradation was observed. © 2019 Elsevier B.V.",
journal = "Journal of Photochemistry and Photobiology A: Chemistry",
title = "Simulated solar light driven performance of nanosized ZnIn2S4/dye system: decolourization vs. photodegradation",
volume = "388",
pages = "112154",
doi = "10.1016/j.jphotochem.2019.112154"
}

Savić, T. D., Carević, M., Mitrić, M., Kuljanin-Jakovljević, J. Ž., Abazović, N.,& Čomor, M.. (2020). Simulated solar light driven performance of nanosized ZnIn2S4/dye system: decolourization vs. photodegradation. in Journal of Photochemistry and Photobiology A: Chemistry, 388, 112154.
https://doi.org/10.1016/j.jphotochem.2019.112154

Savić TD, Carević M, Mitrić M, Kuljanin-Jakovljević JŽ, Abazović N, Čomor M. Simulated solar light driven performance of nanosized ZnIn2S4/dye system: decolourization vs. photodegradation. in Journal of Photochemistry and Photobiology A: Chemistry. 2020;388:112154.
doi:10.1016/j.jphotochem.2019.112154 .

Savić, Tatjana D., Carević, Milica, Mitrić, Miodrag, Kuljanin-Jakovljević, Jadranka Ž., Abazović, Nadica, Čomor, Mirjana, "Simulated solar light driven performance of nanosized ZnIn2S4/dye system: decolourization vs. photodegradation" in Journal of Photochemistry and Photobiology A: Chemistry, 388 (2020):112154,
https://doi.org/10.1016/j.jphotochem.2019.112154 . .

TY  - JOUR
AU  - Carević, Milica
AU  - Savić, Tatjana D.
AU  - Abazović, Nadica
AU  - Mojović, Miloš D.
AU  - Novaković, Tatjana
AU  - Čomor, Mirjana
PY  - 2020
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/8807
AB  - Pure and a series of Fe3+ doped zirconia nanopowders were synthesized combining colloidal chemistry and solvothermal method from organometallic precursors in order to correlate doping and properties of zirconia matrix. After annealing of washed nanopowders at 600 °C, detailed characterization was performed using X-ray diffraction, UV/Vis absorption and luminescence, infrared and electron paramagnetic spectroscopy, transmission electron microscopy and BET measurements. Zirconia samples had mixed monoclinic and tetragonal crystalline phase; increasing Fe3+ ions concentration was followed by increasing of tetragonal phase share. In the sample with highest Fe3+ concentration, hematite can be detected. Also, UV/Vis spectrophotometry showed that Fe3+ doping lowers effective band gap of zirconia matrix from 4.5 eV (bulk value) to 2.1 eV for doped/nanocomposite samples. EPR measurements proved presence of dopant and showed that isolated Fe3+ ions in zirconia matrix exist in both crystalline phases; monoclinic and tetragonal (g 4.8 and g 4.27–4.2, respectively) surroundings. Zirconia samples were also successfully used as photocatalysts for photocatalytic degradation of 2, 4, 6, trichlorophenol. © 2019 Elsevier Ltd and Techna Group S.r.l.
T2  - Ceramics International
T1  - Effect of Fe3+ ion doping on photocatalytic ability of nanozirconia ceramic to degrade 2, 4, 6- trichlorophenol
VL  - 46
IS  - 5
SP  - 6820
EP  - 6827
DO  - 10.1016/j.ceramint.2019.11.175
ER  - 

@article{
author = "Carević, Milica and Savić, Tatjana D. and Abazović, Nadica and Mojović, Miloš D. and Novaković, Tatjana and Čomor, Mirjana",
year = "2020",
abstract = "Pure and a series of Fe3+ doped zirconia nanopowders were synthesized combining colloidal chemistry and solvothermal method from organometallic precursors in order to correlate doping and properties of zirconia matrix. After annealing of washed nanopowders at 600 °C, detailed characterization was performed using X-ray diffraction, UV/Vis absorption and luminescence, infrared and electron paramagnetic spectroscopy, transmission electron microscopy and BET measurements. Zirconia samples had mixed monoclinic and tetragonal crystalline phase; increasing Fe3+ ions concentration was followed by increasing of tetragonal phase share. In the sample with highest Fe3+ concentration, hematite can be detected. Also, UV/Vis spectrophotometry showed that Fe3+ doping lowers effective band gap of zirconia matrix from 4.5 eV (bulk value) to 2.1 eV for doped/nanocomposite samples. EPR measurements proved presence of dopant and showed that isolated Fe3+ ions in zirconia matrix exist in both crystalline phases; monoclinic and tetragonal (g 4.8 and g 4.27–4.2, respectively) surroundings. Zirconia samples were also successfully used as photocatalysts for photocatalytic degradation of 2, 4, 6, trichlorophenol. © 2019 Elsevier Ltd and Techna Group S.r.l.",
journal = "Ceramics International",
title = "Effect of Fe3+ ion doping on photocatalytic ability of nanozirconia ceramic to degrade 2, 4, 6- trichlorophenol",
volume = "46",
number = "5",
pages = "6820-6827",
doi = "10.1016/j.ceramint.2019.11.175"
}

Carević, M., Savić, T. D., Abazović, N., Mojović, M. D., Novaković, T.,& Čomor, M.. (2020). Effect of Fe3+ ion doping on photocatalytic ability of nanozirconia ceramic to degrade 2, 4, 6- trichlorophenol. in Ceramics International, 46(5), 6820-6827.
https://doi.org/10.1016/j.ceramint.2019.11.175

Carević M, Savić TD, Abazović N, Mojović MD, Novaković T, Čomor M. Effect of Fe3+ ion doping on photocatalytic ability of nanozirconia ceramic to degrade 2, 4, 6- trichlorophenol. in Ceramics International. 2020;46(5):6820-6827.
doi:10.1016/j.ceramint.2019.11.175 .

Carević, Milica, Savić, Tatjana D., Abazović, Nadica, Mojović, Miloš D., Novaković, Tatjana, Čomor, Mirjana, "Effect of Fe3+ ion doping on photocatalytic ability of nanozirconia ceramic to degrade 2, 4, 6- trichlorophenol" in Ceramics International, 46, no. 5 (2020):6820-6827,
https://doi.org/10.1016/j.ceramint.2019.11.175 . .

TY  - JOUR
AU  - Novaković, Tatjana
AU  - Abazović, Nadica
AU  - Savić, Tatjana D.
AU  - Čomor, Mirjana
AU  - Mojović, Zorica D.
PY  - 2020
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/9789
AB  - Nickel-alumina composites with various content of nickel were synthetized by sol-gel method. The characterization of samples was performed by diffuse reflectance spectroscopy and electrochemical impedance spectroscopy using the Mott-Schottky analysis. Glassy carbon electrode modified by synthesized composites was investigated for reduction of 4-nitrophenol. Modification of glassy carbon electrode with composite sample led to the strong apparent electrocatalysis. Principal component analysis was used to establish correlation between structural, textural and electrochemical data of investigated composites.
T2  - Science of Sintering
T1  - Application of Ni(II)-alumina Composites for Electrocatalytic Reduction of 4-nitrophenol
VL  - 52
IS  - 3
SP  - 359
EP  - 370
DO  - 10.2298/SOS2003359N
ER  - 

@article{
author = "Novaković, Tatjana and Abazović, Nadica and Savić, Tatjana D. and Čomor, Mirjana and Mojović, Zorica D.",
year = "2020",
abstract = "Nickel-alumina composites with various content of nickel were synthetized by sol-gel method. The characterization of samples was performed by diffuse reflectance spectroscopy and electrochemical impedance spectroscopy using the Mott-Schottky analysis. Glassy carbon electrode modified by synthesized composites was investigated for reduction of 4-nitrophenol. Modification of glassy carbon electrode with composite sample led to the strong apparent electrocatalysis. Principal component analysis was used to establish correlation between structural, textural and electrochemical data of investigated composites.",
journal = "Science of Sintering",
title = "Application of Ni(II)-alumina Composites for Electrocatalytic Reduction of 4-nitrophenol",
volume = "52",
number = "3",
pages = "359-370",
doi = "10.2298/SOS2003359N"
}

Novaković, T., Abazović, N., Savić, T. D., Čomor, M.,& Mojović, Z. D.. (2020). Application of Ni(II)-alumina Composites for Electrocatalytic Reduction of 4-nitrophenol. in Science of Sintering, 52(3), 359-370.
https://doi.org/10.2298/SOS2003359N

Novaković T, Abazović N, Savić TD, Čomor M, Mojović ZD. Application of Ni(II)-alumina Composites for Electrocatalytic Reduction of 4-nitrophenol. in Science of Sintering. 2020;52(3):359-370.
doi:10.2298/SOS2003359N .

Novaković, Tatjana, Abazović, Nadica, Savić, Tatjana D., Čomor, Mirjana, Mojović, Zorica D., "Application of Ni(II)-alumina Composites for Electrocatalytic Reduction of 4-nitrophenol" in Science of Sintering, 52, no. 3 (2020):359-370,
https://doi.org/10.2298/SOS2003359N . .

TY  - JOUR
AU  - Carević, Milica
AU  - Abazović, Nadica
AU  - Savić, Tatjana D.
AU  - Novaković, Tatjana
AU  - Pjević, Dejan J.
AU  - Čomor, Mirjana
PY  - 2018
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/1945
AB  - Solvothermal synthesis of ZrO2-TiO2 binary oxides and pure counterparts at 150 degrees C in water/isopropanol media is presented. Titanium (IV) isopropoxide and zirconium (IV) propoxide were used as precursors. XRD and TEM techniques were used for structural and morphological characterization of obtained samples. XPS spectra of mixed oxide samples were compared in order to correlate composition of samples with surface properties and presence of defects. Relative positions of defect states within band-gaps of semiconductors were estimated from UCPL spectra. UV-Vis DRS spectra revealed that both pure oxides experienced red shift of absorption thresholds compared to reference data. Photocatalytic activities of all samples were probed under simulated Solar light on three model compounds: phenol, 4-chlorophenol (4-CP) and 2, 4, 6-trichlorphenol (TCP). Pure TiO2 showed the highest photocatalytic activity in the case of phenol. However, pure ZrO2 and binary oxides showed higher photoactivity in degradation of 4-CP and TCP. The activity of wide band-gap semiconductors under simulated Solar light in photodegradation of phenol and its derivatives is most probably the consequence of formation of charge transfer complexes between pollutant molecules and semiconductors surface.
T2  - Journal of the American Ceramic Society
T1  - Binary oxide ceramics for enhanced phenols degradation under simulated Solar light
VL  - 101
IS  - 4
SP  - 1420
EP  - 1431
DO  - 10.1111/jace.15324
ER  - 

@article{
author = "Carević, Milica and Abazović, Nadica and Savić, Tatjana D. and Novaković, Tatjana and Pjević, Dejan J. and Čomor, Mirjana",
year = "2018",
abstract = "Solvothermal synthesis of ZrO2-TiO2 binary oxides and pure counterparts at 150 degrees C in water/isopropanol media is presented. Titanium (IV) isopropoxide and zirconium (IV) propoxide were used as precursors. XRD and TEM techniques were used for structural and morphological characterization of obtained samples. XPS spectra of mixed oxide samples were compared in order to correlate composition of samples with surface properties and presence of defects. Relative positions of defect states within band-gaps of semiconductors were estimated from UCPL spectra. UV-Vis DRS spectra revealed that both pure oxides experienced red shift of absorption thresholds compared to reference data. Photocatalytic activities of all samples were probed under simulated Solar light on three model compounds: phenol, 4-chlorophenol (4-CP) and 2, 4, 6-trichlorphenol (TCP). Pure TiO2 showed the highest photocatalytic activity in the case of phenol. However, pure ZrO2 and binary oxides showed higher photoactivity in degradation of 4-CP and TCP. The activity of wide band-gap semiconductors under simulated Solar light in photodegradation of phenol and its derivatives is most probably the consequence of formation of charge transfer complexes between pollutant molecules and semiconductors surface.",
journal = "Journal of the American Ceramic Society",
title = "Binary oxide ceramics for enhanced phenols degradation under simulated Solar light",
volume = "101",
number = "4",
pages = "1420-1431",
doi = "10.1111/jace.15324"
}

Carević, M., Abazović, N., Savić, T. D., Novaković, T., Pjević, D. J.,& Čomor, M.. (2018). Binary oxide ceramics for enhanced phenols degradation under simulated Solar light. in Journal of the American Ceramic Society, 101(4), 1420-1431.
https://doi.org/10.1111/jace.15324

Carević M, Abazović N, Savić TD, Novaković T, Pjević DJ, Čomor M. Binary oxide ceramics for enhanced phenols degradation under simulated Solar light. in Journal of the American Ceramic Society. 2018;101(4):1420-1431.
doi:10.1111/jace.15324 .

Carević, Milica, Abazović, Nadica, Savić, Tatjana D., Novaković, Tatjana, Pjević, Dejan J., Čomor, Mirjana, "Binary oxide ceramics for enhanced phenols degradation under simulated Solar light" in Journal of the American Ceramic Society, 101, no. 4 (2018):1420-1431,
https://doi.org/10.1111/jace.15324 . .

TY  - JOUR
AU  - Carević, Milica
AU  - Savić, Tatjana D.
AU  - Abazović, Nadica
AU  - Mitrić, Miodrag
AU  - Stojanović, Zoran A.
AU  - Ahrenkiel, Scott Phillip
AU  - Čomor, Mirjana
PY  - 2017
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/1397
AB  - Hot-injection method for synthesis of ZnIn2S4 (ZIS) in organic media was studied. Nanosized ZnIn2S4 is successfully synthesized in oleic acid/oleylamine mixture in different ratios, which are both: complexing and/or capping agents. Nanosheets/nanoscrolls of about 50 nm are obtained. The band gaps of synthesized nanostructures were calculated to be in the range from 2.6 to 3.0 eV, values which are increased compared to bulk value (2.3-2.5 eV). The increase of band gap can be assigned to nanodimensions of the particles. Potential of band edges is calculated using empirical equation and find to be in the range from -0.16 to -0.36 V for conduction band, and from 2.24 to 2.69 V for valence band. By using XRD and TEM techniques, crystal structure and morphology of obtained materials were investigated, and detailed formation and growth mechanism of nanosheets/nanoscroles is proposed accordingly. (C) 2016 Elsevier Ltd. All rights reserved.
T2  - Materials Research Bulletin
T1  - Formation of ZnIn2S4 nanosheets and tubular structures in organic media
VL  - 87
SP  - 140
EP  - 147
DO  - 10.1016/j.materresbull.2016.11.037
ER  - 

@article{
author = "Carević, Milica and Savić, Tatjana D. and Abazović, Nadica and Mitrić, Miodrag and Stojanović, Zoran A. and Ahrenkiel, Scott Phillip and Čomor, Mirjana",
year = "2017",
abstract = "Hot-injection method for synthesis of ZnIn2S4 (ZIS) in organic media was studied. Nanosized ZnIn2S4 is successfully synthesized in oleic acid/oleylamine mixture in different ratios, which are both: complexing and/or capping agents. Nanosheets/nanoscrolls of about 50 nm are obtained. The band gaps of synthesized nanostructures were calculated to be in the range from 2.6 to 3.0 eV, values which are increased compared to bulk value (2.3-2.5 eV). The increase of band gap can be assigned to nanodimensions of the particles. Potential of band edges is calculated using empirical equation and find to be in the range from -0.16 to -0.36 V for conduction band, and from 2.24 to 2.69 V for valence band. By using XRD and TEM techniques, crystal structure and morphology of obtained materials were investigated, and detailed formation and growth mechanism of nanosheets/nanoscroles is proposed accordingly. (C) 2016 Elsevier Ltd. All rights reserved.",
journal = "Materials Research Bulletin",
title = "Formation of ZnIn2S4 nanosheets and tubular structures in organic media",
volume = "87",
pages = "140-147",
doi = "10.1016/j.materresbull.2016.11.037"
}

Carević, M., Savić, T. D., Abazović, N., Mitrić, M., Stojanović, Z. A., Ahrenkiel, S. P.,& Čomor, M.. (2017). Formation of ZnIn2S4 nanosheets and tubular structures in organic media. in Materials Research Bulletin, 87, 140-147.
https://doi.org/10.1016/j.materresbull.2016.11.037

Carević M, Savić TD, Abazović N, Mitrić M, Stojanović ZA, Ahrenkiel SP, Čomor M. Formation of ZnIn2S4 nanosheets and tubular structures in organic media. in Materials Research Bulletin. 2017;87:140-147.
doi:10.1016/j.materresbull.2016.11.037 .

Carević, Milica, Savić, Tatjana D., Abazović, Nadica, Mitrić, Miodrag, Stojanović, Zoran A., Ahrenkiel, Scott Phillip, Čomor, Mirjana, "Formation of ZnIn2S4 nanosheets and tubular structures in organic media" in Materials Research Bulletin, 87 (2017):140-147,
https://doi.org/10.1016/j.materresbull.2016.11.037 . .

TY  - CONF
AU  - Pjević, Dejan J.
AU  - Peruško, Davor
AU  - Skoulas, E.
AU  - Stratakis, E.
AU  - Siketić, Z.
AU  - Bogdanović-Radović, Iva
AU  - Savić, Tatjana D.
AU  - Čomor, Mirjana
AU  - Petrović, S.
PY  - 2017
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/10946
AB  - Modification of single titanium and complex titanium-aluminium samples by laser processing in the femtosecond time domain is unexplored field. This work included a study of the effects caused by changes in the composition and morphology of the compact Ti thin film and multilayer Ti/5x(Al/Ti) structure. Titanium and its oxides have specific physical, chemical and mechanical properties, such as high corrosion resistance, good stability, high strength and porosity. Titanium−oxide materials in different types and forms have shown great potential as ideal and powerful photocatalysts for various significant reactions due to their chemical stability, nontoxicity, and high reactivity. Laser surface modification allows production of active surface with formation of the desired oxide, creation of nano/micro textures and change wettability of the surface. The samples were processed by focused an Yb:KGW laser beam with 1026 nm central wavelength, 170 fs pulse duration and repetition rate of 1 kHz. The laser-induced morphological and composition modifications have shown dependence on applied intensities and number of laser pulses. The formed surface nanostructures on the Ti and Ti/Al thin film surface (5x5 mm) are obtained in scanning regime. The results show an increase in surface roughness, formation of parallel periodic surface structures, appearance of hydrodynamic features and ablation of surface material. At low pulse energies range (not over 0.01 mJ) and effective 50 pulses, the two types of LIPSS can be observed: low and high spatial frequency LIPSS (HSFL and LSFL). The low spatial frequency LIPSS (LSFL), oriented perpendicular to the laser polarization with periods slightly lower than the irradiation wavelength, was typically formed. The laser-induced surface oxidation was analysed by Elastic Recoil Detection Analysis (ERDA) in the subsurface part of the investigated samples, which indicates formation Ti-oxide and mixture of Al- and Ti-oxide in the case of multilayer structure. Photocatalytic degradation rate on the laser irradiated surface of Ti and Ti/Al thin films was compared with unmodified samples. The rate of photo-degradation was associated with changes in structure of Ti-oxide and in increasing of surface roughness with formation of periodic structure.
PB  - Belgrade : Institute of Physics Belgrade
C3  - PHOTONICA2017 : 6th International School and Conference on Photonics and COST actions: MP1406 and MP1402 : Program and the book of abstracts
T1  - Laser-induced periodic structure on Ti and Ti/Al thin films for photocatalytic application
SP  - 177
UR  - https://hdl.handle.net/21.15107/rcub_vinar_10946
ER  - 

@conference{
author = "Pjević, Dejan J. and Peruško, Davor and Skoulas, E. and Stratakis, E. and Siketić, Z. and Bogdanović-Radović, Iva and Savić, Tatjana D. and Čomor, Mirjana and Petrović, S.",
year = "2017",
abstract = "Modification of single titanium and complex titanium-aluminium samples by laser processing in the femtosecond time domain is unexplored field. This work included a study of the effects caused by changes in the composition and morphology of the compact Ti thin film and multilayer Ti/5x(Al/Ti) structure. Titanium and its oxides have specific physical, chemical and mechanical properties, such as high corrosion resistance, good stability, high strength and porosity. Titanium−oxide materials in different types and forms have shown great potential as ideal and powerful photocatalysts for various significant reactions due to their chemical stability, nontoxicity, and high reactivity. Laser surface modification allows production of active surface with formation of the desired oxide, creation of nano/micro textures and change wettability of the surface. The samples were processed by focused an Yb:KGW laser beam with 1026 nm central wavelength, 170 fs pulse duration and repetition rate of 1 kHz. The laser-induced morphological and composition modifications have shown dependence on applied intensities and number of laser pulses. The formed surface nanostructures on the Ti and Ti/Al thin film surface (5x5 mm) are obtained in scanning regime. The results show an increase in surface roughness, formation of parallel periodic surface structures, appearance of hydrodynamic features and ablation of surface material. At low pulse energies range (not over 0.01 mJ) and effective 50 pulses, the two types of LIPSS can be observed: low and high spatial frequency LIPSS (HSFL and LSFL). The low spatial frequency LIPSS (LSFL), oriented perpendicular to the laser polarization with periods slightly lower than the irradiation wavelength, was typically formed. The laser-induced surface oxidation was analysed by Elastic Recoil Detection Analysis (ERDA) in the subsurface part of the investigated samples, which indicates formation Ti-oxide and mixture of Al- and Ti-oxide in the case of multilayer structure. Photocatalytic degradation rate on the laser irradiated surface of Ti and Ti/Al thin films was compared with unmodified samples. The rate of photo-degradation was associated with changes in structure of Ti-oxide and in increasing of surface roughness with formation of periodic structure.",
publisher = "Belgrade : Institute of Physics Belgrade",
journal = "PHOTONICA2017 : 6th International School and Conference on Photonics and COST actions: MP1406 and MP1402 : Program and the book of abstracts",
title = "Laser-induced periodic structure on Ti and Ti/Al thin films for photocatalytic application",
pages = "177",
url = "https://hdl.handle.net/21.15107/rcub_vinar_10946"
}

Pjević, D. J., Peruško, D., Skoulas, E., Stratakis, E., Siketić, Z., Bogdanović-Radović, I., Savić, T. D., Čomor, M.,& Petrović, S.. (2017). Laser-induced periodic structure on Ti and Ti/Al thin films for photocatalytic application. in PHOTONICA2017 : 6th International School and Conference on Photonics and COST actions: MP1406 and MP1402 : Program and the book of abstracts
Belgrade : Institute of Physics Belgrade., 177.
https://hdl.handle.net/21.15107/rcub_vinar_10946

Pjević DJ, Peruško D, Skoulas E, Stratakis E, Siketić Z, Bogdanović-Radović I, Savić TD, Čomor M, Petrović S. Laser-induced periodic structure on Ti and Ti/Al thin films for photocatalytic application. in PHOTONICA2017 : 6th International School and Conference on Photonics and COST actions: MP1406 and MP1402 : Program and the book of abstracts. 2017;:177.
https://hdl.handle.net/21.15107/rcub_vinar_10946 .

Pjević, Dejan J., Peruško, Davor, Skoulas, E., Stratakis, E., Siketić, Z., Bogdanović-Radović, Iva, Savić, Tatjana D., Čomor, Mirjana, Petrović, S., "Laser-induced periodic structure on Ti and Ti/Al thin films for photocatalytic application" in PHOTONICA2017 : 6th International School and Conference on Photonics and COST actions: MP1406 and MP1402 : Program and the book of abstracts (2017):177,
https://hdl.handle.net/21.15107/rcub_vinar_10946 .

TY  - JOUR
AU  - Carević, Milica
AU  - Abazović, Nadica
AU  - Savić, Tatjana D.
AU  - Novaković, Tatjana
AU  - Mojovic, Milos D.
AU  - Čomor, Mirjana
PY  - 2016
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/823
AB  - We report the successful, low temperature synthesis of pure and Fe-doped titania nanoparticle (NP) powders, using organic Ti- and Fe-precursors. The properties of the synthesized titania based materials were obtained using XRD, UV/vis and EPR spectroscopy and BET measurements. The doping of TiO2 induced a shift in the absorption threshold towards the visible spectral range, compared to pure titania. The process of annealing induced an increase in crystallinity and particle sizes in the obtained materials. The photocatalytic activity, using simulated Solar light (Vitalux lamp), of our samples was checked by following the photodegradation reaction of Rhodamine B and trichlorophenole as model compounds. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.
PB  - Elsevier
T2  - Ceramics International
T1  - Structural, optical and photodegradation properties of pure and Fe-doped titania nanoparticles probed using simulated Solar light
VL  - 42
IS  - 1
SP  - 1521
EP  - 1529
DO  - 10.1016/j.ceramint.2015.09.100
ER  - 

@article{
author = "Carević, Milica and Abazović, Nadica and Savić, Tatjana D. and Novaković, Tatjana and Mojovic, Milos D. and Čomor, Mirjana",
year = "2016",
abstract = "We report the successful, low temperature synthesis of pure and Fe-doped titania nanoparticle (NP) powders, using organic Ti- and Fe-precursors. The properties of the synthesized titania based materials were obtained using XRD, UV/vis and EPR spectroscopy and BET measurements. The doping of TiO2 induced a shift in the absorption threshold towards the visible spectral range, compared to pure titania. The process of annealing induced an increase in crystallinity and particle sizes in the obtained materials. The photocatalytic activity, using simulated Solar light (Vitalux lamp), of our samples was checked by following the photodegradation reaction of Rhodamine B and trichlorophenole as model compounds. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.",
publisher = "Elsevier",
journal = "Ceramics International",
title = "Structural, optical and photodegradation properties of pure and Fe-doped titania nanoparticles probed using simulated Solar light",
volume = "42",
number = "1",
pages = "1521-1529",
doi = "10.1016/j.ceramint.2015.09.100"
}

Carević, M., Abazović, N., Savić, T. D., Novaković, T., Mojovic, M. D.,& Čomor, M.. (2016). Structural, optical and photodegradation properties of pure and Fe-doped titania nanoparticles probed using simulated Solar light. in Ceramics International
Elsevier., 42(1), 1521-1529.
https://doi.org/10.1016/j.ceramint.2015.09.100

Carević M, Abazović N, Savić TD, Novaković T, Mojovic MD, Čomor M. Structural, optical and photodegradation properties of pure and Fe-doped titania nanoparticles probed using simulated Solar light. in Ceramics International. 2016;42(1):1521-1529.
doi:10.1016/j.ceramint.2015.09.100 .

Carević, Milica, Abazović, Nadica, Savić, Tatjana D., Novaković, Tatjana, Mojovic, Milos D., Čomor, Mirjana, "Structural, optical and photodegradation properties of pure and Fe-doped titania nanoparticles probed using simulated Solar light" in Ceramics International, 42, no. 1 (2016):1521-1529,
https://doi.org/10.1016/j.ceramint.2015.09.100 . .

TY  - CONF
AU  - Carević, Milica
AU  - Čomor, Mirjana
AU  - Savić, Tatjana D.
AU  - Ahrenkiel, Scott Phillip
AU  - Abazović, Nadica
PY  - 2016
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/9215
AB  - Ternary  nanosized  sulfide  CdIn2S4was  synthesized  using  hot-injectionmethod  in  oleic  acid/oleylamine  mixture  as  reaction  media  at  270ºC.  TEM images have shown that obtained material grows through multistep process, forming  marigold  structures  built  out  from  mesocrystals.  Influence  of  oleic acid  and  oleic  acid/oleylaminemixture  as  reaction  media  on  mesocrystal formation is tracked and discussed.
PB  - Society of Physical Chemists of Serbia
C3  - Physical chemistry 2016 : 13th international conference on fundamental and applied aspects of physical chemistry
T1  - Synthesis of CdIn2S4 mesocrystals
SP  - 545
EP  - 548
UR  - https://hdl.handle.net/21.15107/rcub_vinar_9215
ER  - 

@conference{
author = "Carević, Milica and Čomor, Mirjana and Savić, Tatjana D. and Ahrenkiel, Scott Phillip and Abazović, Nadica",
year = "2016",
abstract = "Ternary  nanosized  sulfide  CdIn2S4was  synthesized  using  hot-injectionmethod  in  oleic  acid/oleylamine  mixture  as  reaction  media  at  270ºC.  TEM images have shown that obtained material grows through multistep process, forming  marigold  structures  built  out  from  mesocrystals.  Influence  of  oleic acid  and  oleic  acid/oleylaminemixture  as  reaction  media  on  mesocrystal formation is tracked and discussed.",
publisher = "Society of Physical Chemists of Serbia",
journal = "Physical chemistry 2016 : 13th international conference on fundamental and applied aspects of physical chemistry",
title = "Synthesis of CdIn2S4 mesocrystals",
pages = "545-548",
url = "https://hdl.handle.net/21.15107/rcub_vinar_9215"
}

Carević, M., Čomor, M., Savić, T. D., Ahrenkiel, S. P.,& Abazović, N.. (2016). Synthesis of CdIn2S4 mesocrystals. in Physical chemistry 2016 : 13th international conference on fundamental and applied aspects of physical chemistry
Society of Physical Chemists of Serbia., 545-548.
https://hdl.handle.net/21.15107/rcub_vinar_9215

Carević M, Čomor M, Savić TD, Ahrenkiel SP, Abazović N. Synthesis of CdIn2S4 mesocrystals. in Physical chemistry 2016 : 13th international conference on fundamental and applied aspects of physical chemistry. 2016;:545-548.
https://hdl.handle.net/21.15107/rcub_vinar_9215 .

Carević, Milica, Čomor, Mirjana, Savić, Tatjana D., Ahrenkiel, Scott Phillip, Abazović, Nadica, "Synthesis of CdIn2S4 mesocrystals" in Physical chemistry 2016 : 13th international conference on fundamental and applied aspects of physical chemistry (2016):545-548,
https://hdl.handle.net/21.15107/rcub_vinar_9215 .

TY  - CONF
AU  - Savić, Tatjana D.
AU  - Čomor, Mirjana
AU  - Janković, Ivana A.
AU  - Rakić, Vesna M.
AU  - Abazović, Nadica
AU  - Carević, Milica
PY  - 2016
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/9216
AB  - The  surface  modification  of  nanocrystalline  TiO2particles  (45  Å)  with salicylate-type  ligands  consisting  of  anextended  aromatic  ring  system, specifically   1-hydroxy-2-naphthoicacid(1H2NA)and   1,4-dihydroxy-2-naphthoicacid(1,4DH2NA),  was  found  to  alter  the  optical  properties  of nanoparticles  in  a  similar  way  to  salicylic  acid(2HBA).The  formation  of the inner-sphere charge-transfer(CT) complexes results in a red shift of the semiconductor  absorptiononsetcompared  to  unmodified nanocrystallitesand   a   reduction   in   the   band   gap   upon   the   increase   in   the   electron delocalization   when   including   an   additional   ring.From absorption measurements of   CT   complexes   in   methanol/water=90/10   solutions, stability  constants  in  the  order  of  103M-1havebeen  determined  at  pH  2.Thermal stability of CT-complexes was investigated by using TPD analysis (TG/DTA/MS).
PB  - Society of Physical Chemists of Serbia
C3  - Physical chemistry 2016 : 13th international conference on fundamental and applied aspects of physical chemistry
T1  - Thermal stability of CT-complexes formed at the surface of anatase nanoparticles
SP  - 549
EP  - 552
UR  - https://hdl.handle.net/21.15107/rcub_vinar_9216
ER  - 

@conference{
author = "Savić, Tatjana D. and Čomor, Mirjana and Janković, Ivana A. and Rakić, Vesna M. and Abazović, Nadica and Carević, Milica",
year = "2016",
abstract = "The  surface  modification  of  nanocrystalline  TiO2particles  (45  Å)  with salicylate-type  ligands  consisting  of  anextended  aromatic  ring  system, specifically   1-hydroxy-2-naphthoicacid(1H2NA)and   1,4-dihydroxy-2-naphthoicacid(1,4DH2NA),  was  found  to  alter  the  optical  properties  of nanoparticles  in  a  similar  way  to  salicylic  acid(2HBA).The  formation  of the inner-sphere charge-transfer(CT) complexes results in a red shift of the semiconductor  absorptiononsetcompared  to  unmodified nanocrystallitesand   a   reduction   in   the   band   gap   upon   the   increase   in   the   electron delocalization   when   including   an   additional   ring.From absorption measurements of   CT   complexes   in   methanol/water=90/10   solutions, stability  constants  in  the  order  of  103M-1havebeen  determined  at  pH  2.Thermal stability of CT-complexes was investigated by using TPD analysis (TG/DTA/MS).",
publisher = "Society of Physical Chemists of Serbia",
journal = "Physical chemistry 2016 : 13th international conference on fundamental and applied aspects of physical chemistry",
title = "Thermal stability of CT-complexes formed at the surface of anatase nanoparticles",
pages = "549-552",
url = "https://hdl.handle.net/21.15107/rcub_vinar_9216"
}

Savić, T. D., Čomor, M., Janković, I. A., Rakić, V. M., Abazović, N.,& Carević, M.. (2016). Thermal stability of CT-complexes formed at the surface of anatase nanoparticles. in Physical chemistry 2016 : 13th international conference on fundamental and applied aspects of physical chemistry
Society of Physical Chemists of Serbia., 549-552.
https://hdl.handle.net/21.15107/rcub_vinar_9216

Savić TD, Čomor M, Janković IA, Rakić VM, Abazović N, Carević M. Thermal stability of CT-complexes formed at the surface of anatase nanoparticles. in Physical chemistry 2016 : 13th international conference on fundamental and applied aspects of physical chemistry. 2016;:549-552.
https://hdl.handle.net/21.15107/rcub_vinar_9216 .

Savić, Tatjana D., Čomor, Mirjana, Janković, Ivana A., Rakić, Vesna M., Abazović, Nadica, Carević, Milica, "Thermal stability of CT-complexes formed at the surface of anatase nanoparticles" in Physical chemistry 2016 : 13th international conference on fundamental and applied aspects of physical chemistry (2016):549-552,
https://hdl.handle.net/21.15107/rcub_vinar_9216 .

TY  - CONF
AU  - Carević, Milica
AU  - Abazović, Nadica
AU  - Savić, Tatjana D.
AU  - Novaković, Tatjana
AU  - Čomor, Mirjana
PY  - 2016
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/9217
AB  - In this paper,a hydrothermal method for synthesis of zirconia nanopowders: pure  and  with  incorporated  Si4+ions  is  presented.  Zirconyl  chloride  and tetraethyl  orthosilicate  were  used  as  precursors.  As  prepared  powders  were annealed  at  600  °C  and  their  structural  (XRD),  morphological  (TEM)  and textural  (BET  method)  properties  were  obtained.It  has  been  shown  that  by using   hydrothermal   synthesis   method   pure   monoclinic   ZrO2highly crystalline    powder    can    be    obtainedwithcrystallites    of    about    25nm. Incorporation  of  Si4+ions  induced  stabilization  of  tetragonal  crystalline phase  at  room  temperature,  decreasing  particle  sizes  to  about  3-6  nm  and increasing specific surface area of nanopowders.
PB  - Society of Physical Chemists of Serbia
C3  - Physical chemistry 2016 : 13th international conference on fundamental and applied aspects of physical chemistry
T1  - Characterization of hydrothermaly synthesized zirconia nanopowders
SP  - 553
EP  - 556
UR  - https://hdl.handle.net/21.15107/rcub_vinar_9217
ER  - 

@conference{
author = "Carević, Milica and Abazović, Nadica and Savić, Tatjana D. and Novaković, Tatjana and Čomor, Mirjana",
year = "2016",
abstract = "In this paper,a hydrothermal method for synthesis of zirconia nanopowders: pure  and  with  incorporated  Si4+ions  is  presented.  Zirconyl  chloride  and tetraethyl  orthosilicate  were  used  as  precursors.  As  prepared  powders  were annealed  at  600  °C  and  their  structural  (XRD),  morphological  (TEM)  and textural  (BET  method)  properties  were  obtained.It  has  been  shown  that  by using   hydrothermal   synthesis   method   pure   monoclinic   ZrO2highly crystalline    powder    can    be    obtainedwithcrystallites    of    about    25nm. Incorporation  of  Si4+ions  induced  stabilization  of  tetragonal  crystalline phase  at  room  temperature,  decreasing  particle  sizes  to  about  3-6  nm  and increasing specific surface area of nanopowders.",
publisher = "Society of Physical Chemists of Serbia",
journal = "Physical chemistry 2016 : 13th international conference on fundamental and applied aspects of physical chemistry",
title = "Characterization of hydrothermaly synthesized zirconia nanopowders",
pages = "553-556",
url = "https://hdl.handle.net/21.15107/rcub_vinar_9217"
}

Carević, M., Abazović, N., Savić, T. D., Novaković, T.,& Čomor, M.. (2016). Characterization of hydrothermaly synthesized zirconia nanopowders. in Physical chemistry 2016 : 13th international conference on fundamental and applied aspects of physical chemistry
Society of Physical Chemists of Serbia., 553-556.
https://hdl.handle.net/21.15107/rcub_vinar_9217

Carević M, Abazović N, Savić TD, Novaković T, Čomor M. Characterization of hydrothermaly synthesized zirconia nanopowders. in Physical chemistry 2016 : 13th international conference on fundamental and applied aspects of physical chemistry. 2016;:553-556.
https://hdl.handle.net/21.15107/rcub_vinar_9217 .

Carević, Milica, Abazović, Nadica, Savić, Tatjana D., Novaković, Tatjana, Čomor, Mirjana, "Characterization of hydrothermaly synthesized zirconia nanopowders" in Physical chemistry 2016 : 13th international conference on fundamental and applied aspects of physical chemistry (2016):553-556,
https://hdl.handle.net/21.15107/rcub_vinar_9217 .

TY  - THES
AU  - Savić, Tatjana D.
PY  - 2015
UR  - http://eteze.bg.ac.rs/application/showtheses?thesesId=3219
UR  - https://fedorabg.bg.ac.rs/fedora/get/o:11639/bdef:Content/download
UR  - http://vbs.rs/scripts/cobiss?command=DISPLAY&base=70036&RID=47648527
UR  - http://nardus.mpn.gov.rs/123456789/5876
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/7289
AB  - U poslednjih 30 godina nanokristalni TiO2 je privukao veliku paţnju kako kao fotokatalizator za različite praktične primene, tako i kao deo fotohemijskih sistema, kao što je Grecelova ćelija. Zbog svog velikog energetskog procepa (Eg=3,2 eV), TiO2 apsorbuje manje od 5 % dostupnih fotona sunčeve svetlosti, što ga čini relativno neefikasnim fotokatalizatorom. Takođe, glavni energetski gubitak nastaje usled procesa radijativne ili neradijativne rekombinacije naelektrisanja nastalih fotoekscitacijom TiO2, što se manifestuje kao relativno nizak prinos dugo-ţivećih razdvojenih naelektrisanja. Dakle, uspešna fotohemijska konverzija energije i reakcije koje slede zahtevaju produţeno vreme ţivota razdvojenih fotostvorenih naelektrisanja kao i apsorpciju u vidljivom delu spektra...
AB  - In the last 30 years nanocrystalline TiO2 has attracted widespread attention as a photocatalyst in various practical applications as well as the part of photoelectrochemical systems, such as Grätzel cells. Due to its large band gap (Eg = 3,2 eV), TiO2 absorbs less than 5% of the available solar light photons, being a relatively inefficient photocatalyst. Also, the main energy loss is due to the process of radiative or nonradiative recombination of charges generated upon photoexcitation of TiO2, which is manifested as the relatively low yield of long-lived separated charges. Hence, the successful photochemical energy conversion and subsequent chemical reactions require both the extended lifetime of separated photogenerated charges and the response in the visible spectral region...
PB  - Универзитет у Београду, Факултет за физичку хемију
T2  - Универзитет у Београду
T1  - Sinteza i karakterizacija nanočestica titan(IV) oksida modifikovanih ligandima kateholatnog i salicilatnog tipa: eksperimentalna i teorijska (DFT) studija
T1  - Synthesis and characterization of titanium(IV) oxide nanoparticles modified with catecholate and salicylate type ligands: experimental and theoretical (DFT) study
UR  - https://hdl.handle.net/21.15107/rcub_nardus_5876
ER  - 

@phdthesis{
author = "Savić, Tatjana D.",
year = "2015",
abstract = "U poslednjih 30 godina nanokristalni TiO2 je privukao veliku paţnju kako kao fotokatalizator za različite praktične primene, tako i kao deo fotohemijskih sistema, kao što je Grecelova ćelija. Zbog svog velikog energetskog procepa (Eg=3,2 eV), TiO2 apsorbuje manje od 5 % dostupnih fotona sunčeve svetlosti, što ga čini relativno neefikasnim fotokatalizatorom. Takođe, glavni energetski gubitak nastaje usled procesa radijativne ili neradijativne rekombinacije naelektrisanja nastalih fotoekscitacijom TiO2, što se manifestuje kao relativno nizak prinos dugo-ţivećih razdvojenih naelektrisanja. Dakle, uspešna fotohemijska konverzija energije i reakcije koje slede zahtevaju produţeno vreme ţivota razdvojenih fotostvorenih naelektrisanja kao i apsorpciju u vidljivom delu spektra..., In the last 30 years nanocrystalline TiO2 has attracted widespread attention as a photocatalyst in various practical applications as well as the part of photoelectrochemical systems, such as Grätzel cells. Due to its large band gap (Eg = 3,2 eV), TiO2 absorbs less than 5% of the available solar light photons, being a relatively inefficient photocatalyst. Also, the main energy loss is due to the process of radiative or nonradiative recombination of charges generated upon photoexcitation of TiO2, which is manifested as the relatively low yield of long-lived separated charges. Hence, the successful photochemical energy conversion and subsequent chemical reactions require both the extended lifetime of separated photogenerated charges and the response in the visible spectral region...",
publisher = "Универзитет у Београду, Факултет за физичку хемију",
journal = "Универзитет у Београду",
title = "Sinteza i karakterizacija nanočestica titan(IV) oksida modifikovanih ligandima kateholatnog i salicilatnog tipa: eksperimentalna i teorijska (DFT) studija, Synthesis and characterization of titanium(IV) oxide nanoparticles modified with catecholate and salicylate type ligands: experimental and theoretical (DFT) study",
url = "https://hdl.handle.net/21.15107/rcub_nardus_5876"
}

Savić, T. D.. (2015). Sinteza i karakterizacija nanočestica titan(IV) oksida modifikovanih ligandima kateholatnog i salicilatnog tipa: eksperimentalna i teorijska (DFT) studija. in Универзитет у Београду
Универзитет у Београду, Факултет за физичку хемију..
https://hdl.handle.net/21.15107/rcub_nardus_5876

Savić TD. Sinteza i karakterizacija nanočestica titan(IV) oksida modifikovanih ligandima kateholatnog i salicilatnog tipa: eksperimentalna i teorijska (DFT) studija. in Универзитет у Београду. 2015;.
https://hdl.handle.net/21.15107/rcub_nardus_5876 .

Savić, Tatjana D., "Sinteza i karakterizacija nanočestica titan(IV) oksida modifikovanih ligandima kateholatnog i salicilatnog tipa: eksperimentalna i teorijska (DFT) studija" in Универзитет у Београду (2015),
https://hdl.handle.net/21.15107/rcub_nardus_5876 .

TY  - JOUR
AU  - Savić, Tatjana D.
AU  - Čomor, Mirjana
AU  - Abazović, Nadica
AU  - Šaponjić, Zoran
AU  - Marinović-Cincović, Milena
AU  - Veljkovic, Dusan Z.
AU  - Zarić, Snežana D.
AU  - Janković, Ivana A.
PY  - 2015
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/410
AB  - Sensitization of TiO2 crystals and nanoparticles with appropriately chosen organic molecules can lead to a significant shift of their absorption threshold from the UV to the visible, thus improving the absorption of the solar spectrum as well as the efficiency of photocatalytic and photovoltaic devices. Herein, the surface modification of nanocrystalline TiO2 particles (45 angstrom) with salicylate-type ligands consisting of an extended aromatic ring system, specifically 1-hydroxy-2-naphthoic acid and 1,4-dihydroxy-2-naphthoic acid, was found to alter the optical properties of nanoparticles in a similar way to salicylic acid. From both absorption measurements and steady-state quenching measurements of modifier fluorescence upon binding to TiO2 in methanol/ water = 90/10 solutions, stability constants in the order of 10(3) M-1 have been determined at pH 2. Fluorescence lifetime measurements, in the presence and absence of colloidal TiO2 nanoparticles, indicated that the fluorescence quenching process is primarily static quenching, thus proving the formation of a nonfluorescent charge-transfer (CT) complex. The binding structures were investigated by using FTIR spectroscopy. Thermal stability of CT-complexes was investigated by using TPD analysis (TG/DTA/MS). Quantum chemical calculations on model systems using density functional theory (DFT) were performed to obtain the vibrational frequencies of charge transfer complexes, and the calculated values were compared with the experimental data. The investigated ligands have the optimal geometry for binding to surface Ti atoms, resulting in ring coordination complexes of a salicylate type (binuclear bidentate binding-bridging) thus restoring the six-coordinated octahedral geometry of surface Ti atoms. The formation of the inner-sphere CT-complexes results in a red shift of the semiconductor absorption compared to unmodified nanocrystallites and a reduction in the band gap upon the increase in the electron delocalization when including an additional ring. (C) 2015 Elsevier B.V. All rights reserved.
T2  - Journal of Alloys and Compounds
T1  - Anatase nanoparticles surface modified with fused ring salicylate-type ligands (1-hydroxy-2-naphthoic acids): A combined DFT and experimental study
VL  - 630
SP  - 226
EP  - 235
DO  - 10.1016/j.jallcom.2015.01.041
ER  - 

@article{
author = "Savić, Tatjana D. and Čomor, Mirjana and Abazović, Nadica and Šaponjić, Zoran and Marinović-Cincović, Milena and Veljkovic, Dusan Z. and Zarić, Snežana D. and Janković, Ivana A.",
year = "2015",
abstract = "Sensitization of TiO2 crystals and nanoparticles with appropriately chosen organic molecules can lead to a significant shift of their absorption threshold from the UV to the visible, thus improving the absorption of the solar spectrum as well as the efficiency of photocatalytic and photovoltaic devices. Herein, the surface modification of nanocrystalline TiO2 particles (45 angstrom) with salicylate-type ligands consisting of an extended aromatic ring system, specifically 1-hydroxy-2-naphthoic acid and 1,4-dihydroxy-2-naphthoic acid, was found to alter the optical properties of nanoparticles in a similar way to salicylic acid. From both absorption measurements and steady-state quenching measurements of modifier fluorescence upon binding to TiO2 in methanol/ water = 90/10 solutions, stability constants in the order of 10(3) M-1 have been determined at pH 2. Fluorescence lifetime measurements, in the presence and absence of colloidal TiO2 nanoparticles, indicated that the fluorescence quenching process is primarily static quenching, thus proving the formation of a nonfluorescent charge-transfer (CT) complex. The binding structures were investigated by using FTIR spectroscopy. Thermal stability of CT-complexes was investigated by using TPD analysis (TG/DTA/MS). Quantum chemical calculations on model systems using density functional theory (DFT) were performed to obtain the vibrational frequencies of charge transfer complexes, and the calculated values were compared with the experimental data. The investigated ligands have the optimal geometry for binding to surface Ti atoms, resulting in ring coordination complexes of a salicylate type (binuclear bidentate binding-bridging) thus restoring the six-coordinated octahedral geometry of surface Ti atoms. The formation of the inner-sphere CT-complexes results in a red shift of the semiconductor absorption compared to unmodified nanocrystallites and a reduction in the band gap upon the increase in the electron delocalization when including an additional ring. (C) 2015 Elsevier B.V. All rights reserved.",
journal = "Journal of Alloys and Compounds",
title = "Anatase nanoparticles surface modified with fused ring salicylate-type ligands (1-hydroxy-2-naphthoic acids): A combined DFT and experimental study",
volume = "630",
pages = "226-235",
doi = "10.1016/j.jallcom.2015.01.041"
}

Savić, T. D., Čomor, M., Abazović, N., Šaponjić, Z., Marinović-Cincović, M., Veljkovic, D. Z., Zarić, S. D.,& Janković, I. A.. (2015). Anatase nanoparticles surface modified with fused ring salicylate-type ligands (1-hydroxy-2-naphthoic acids): A combined DFT and experimental study. in Journal of Alloys and Compounds, 630, 226-235.
https://doi.org/10.1016/j.jallcom.2015.01.041

Savić TD, Čomor M, Abazović N, Šaponjić Z, Marinović-Cincović M, Veljkovic DZ, Zarić SD, Janković IA. Anatase nanoparticles surface modified with fused ring salicylate-type ligands (1-hydroxy-2-naphthoic acids): A combined DFT and experimental study. in Journal of Alloys and Compounds. 2015;630:226-235.
doi:10.1016/j.jallcom.2015.01.041 .

Savić, Tatjana D., Čomor, Mirjana, Abazović, Nadica, Šaponjić, Zoran, Marinović-Cincović, Milena, Veljkovic, Dusan Z., Zarić, Snežana D., Janković, Ivana A., "Anatase nanoparticles surface modified with fused ring salicylate-type ligands (1-hydroxy-2-naphthoic acids): A combined DFT and experimental study" in Journal of Alloys and Compounds, 630 (2015):226-235,
https://doi.org/10.1016/j.jallcom.2015.01.041 . .

TY  - CONF
AU  - Carević, Milica
AU  - Savić, Tatjana D.
AU  - Abazović, Nadica
AU  - Janković, Ivana A.
AU  - Čomor, Mirjana
PY  - 2014
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/9236
AB  - The colloidal ZrO2 nanoparticles were hydrolytically synthesized and
characterized using x-ray diffraction and UV/Vis spectroscopy. The surface
modification of nanocrystalline particles with selected enediol ligands:
catechol (CAT), 2,3-dihydroxynaphthalene (2,3-DHN), anthrarobin (ANT)
and quercetin, was found to alter the optical properties of nanoparticles. The
formation of the inner-sphere charge-transfer (CT) complexes results in a
red shift of the semiconductor absorption onset compared to unmodified
nanocrystallites, and a decrease of effective band gap upon increase of the
electron delocalization after the inclusion of additional rings
PB  - Society of Physical Chemists of Serbia
C3  - Physical chemistry 2014: 12th International Conference on Fundamental and Applied Aspects of Physical Chemistry
T1  - Surface modification of zirconia nanoparticles with selected enediol ligands
VL  - H-23-P
UR  - https://hdl.handle.net/21.15107/rcub_vinar_9236
ER  - 

@conference{
author = "Carević, Milica and Savić, Tatjana D. and Abazović, Nadica and Janković, Ivana A. and Čomor, Mirjana",
year = "2014",
abstract = "The colloidal ZrO2 nanoparticles were hydrolytically synthesized and
characterized using x-ray diffraction and UV/Vis spectroscopy. The surface
modification of nanocrystalline particles with selected enediol ligands:
catechol (CAT), 2,3-dihydroxynaphthalene (2,3-DHN), anthrarobin (ANT)
and quercetin, was found to alter the optical properties of nanoparticles. The
formation of the inner-sphere charge-transfer (CT) complexes results in a
red shift of the semiconductor absorption onset compared to unmodified
nanocrystallites, and a decrease of effective band gap upon increase of the
electron delocalization after the inclusion of additional rings",
publisher = "Society of Physical Chemists of Serbia",
journal = "Physical chemistry 2014: 12th International Conference on Fundamental and Applied Aspects of Physical Chemistry",
title = "Surface modification of zirconia nanoparticles with selected enediol ligands",
volume = "H-23-P",
url = "https://hdl.handle.net/21.15107/rcub_vinar_9236"
}

Carević, M., Savić, T. D., Abazović, N., Janković, I. A.,& Čomor, M.. (2014). Surface modification of zirconia nanoparticles with selected enediol ligands. in Physical chemistry 2014: 12th International Conference on Fundamental and Applied Aspects of Physical Chemistry
Society of Physical Chemists of Serbia., H-23-P.
https://hdl.handle.net/21.15107/rcub_vinar_9236

Carević M, Savić TD, Abazović N, Janković IA, Čomor M. Surface modification of zirconia nanoparticles with selected enediol ligands. in Physical chemistry 2014: 12th International Conference on Fundamental and Applied Aspects of Physical Chemistry. 2014;H-23-P.
https://hdl.handle.net/21.15107/rcub_vinar_9236 .

Carević, Milica, Savić, Tatjana D., Abazović, Nadica, Janković, Ivana A., Čomor, Mirjana, "Surface modification of zirconia nanoparticles with selected enediol ligands" in Physical chemistry 2014: 12th International Conference on Fundamental and Applied Aspects of Physical Chemistry, H-23-P (2014),
https://hdl.handle.net/21.15107/rcub_vinar_9236 .

TY  - CONF
AU  - Savić, Tatjana D.
AU  - Čomor, Mirjana
AU  - Tešević, Vele V.
AU  - Janković, Ivana A.
PY  - 2014
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/9230
AB  - The surface modification of nanocrystalline TiO2 particles (45 Å) with
catecholate-type ligands having electron donating (4-methylcatechol,
4MetCat) and electron withdrawing (4-nitrocatechol, 4NitCat) substituent
groups, was found to alter the optical properties of nanoparticles in a similar
way to catechol (Cat). The formation of the inner-sphere charge-transfer
(CT) complexes results in a red shift of the semiconductor absorption onset
compared to unmodified nanocrystallites, being slightly less pronounced in
the case of electron withdrawing substituent. The investigated ligands have
the optimal geometry for binding to surface Ti atoms, resulting in ring
coordination complexes of catecholate type (binuclear bidentate binding -
bridging) thus restoring six-coordinated octahedral geometry of surface Ti
atoms. The binding structures were investigated by using FTIR
spectroscopy.
PB  - Society of Physical Chemists of Serbia
C3  - Physical chemistry 2014: 12th International Conference on Fundamental and Applied Aspects of Physical Chemistry
T1  - Surface modification of anatase nanoparticles with substituted catecholate type ligands
VL  - H-08-P
UR  - https://hdl.handle.net/21.15107/rcub_vinar_9230
ER  - 

@conference{
author = "Savić, Tatjana D. and Čomor, Mirjana and Tešević, Vele V. and Janković, Ivana A.",
year = "2014",
abstract = "The surface modification of nanocrystalline TiO2 particles (45 Å) with
catecholate-type ligands having electron donating (4-methylcatechol,
4MetCat) and electron withdrawing (4-nitrocatechol, 4NitCat) substituent
groups, was found to alter the optical properties of nanoparticles in a similar
way to catechol (Cat). The formation of the inner-sphere charge-transfer
(CT) complexes results in a red shift of the semiconductor absorption onset
compared to unmodified nanocrystallites, being slightly less pronounced in
the case of electron withdrawing substituent. The investigated ligands have
the optimal geometry for binding to surface Ti atoms, resulting in ring
coordination complexes of catecholate type (binuclear bidentate binding -
bridging) thus restoring six-coordinated octahedral geometry of surface Ti
atoms. The binding structures were investigated by using FTIR
spectroscopy.",
publisher = "Society of Physical Chemists of Serbia",
journal = "Physical chemistry 2014: 12th International Conference on Fundamental and Applied Aspects of Physical Chemistry",
title = "Surface modification of anatase nanoparticles with substituted catecholate type ligands",
volume = "H-08-P",
url = "https://hdl.handle.net/21.15107/rcub_vinar_9230"
}

Savić, T. D., Čomor, M., Tešević, V. V.,& Janković, I. A.. (2014). Surface modification of anatase nanoparticles with substituted catecholate type ligands. in Physical chemistry 2014: 12th International Conference on Fundamental and Applied Aspects of Physical Chemistry
Society of Physical Chemists of Serbia., H-08-P.
https://hdl.handle.net/21.15107/rcub_vinar_9230

Savić TD, Čomor M, Tešević VV, Janković IA. Surface modification of anatase nanoparticles with substituted catecholate type ligands. in Physical chemistry 2014: 12th International Conference on Fundamental and Applied Aspects of Physical Chemistry. 2014;H-08-P.
https://hdl.handle.net/21.15107/rcub_vinar_9230 .

Savić, Tatjana D., Čomor, Mirjana, Tešević, Vele V., Janković, Ivana A., "Surface modification of anatase nanoparticles with substituted catecholate type ligands" in Physical chemistry 2014: 12th International Conference on Fundamental and Applied Aspects of Physical Chemistry, H-08-P (2014),
https://hdl.handle.net/21.15107/rcub_vinar_9230 .

TY  - JOUR
AU  - Savić, Tatjana D.
AU  - Čomor, Mirjana
AU  - Nedeljković, Jovan
AU  - Veljkovic, Dusan Z.
AU  - Zarić, Snežana D.
AU  - Rakić, Vesna M.
AU  - Janković, Ivana A.
PY  - 2014
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/125
AB  - The surface modification of nanocrystalline TiO2 particles (45 angstrom) with catecholate-type ligands having different electron donating/electron withdrawing substituent groups, specifically 3-methylcatechol, 4-methylcatechol, 3-methoxycatechol, 3,4-dihydroxybenzaldehyde and 4-nitrocatechol, was found to alter the optical properties of nanoparticles in a similar way to catechol. The formation of the inner-sphere charge-transfer (CT) complexes results in a red shift of the semiconductor absorption compared to unmodified nanocrystallites and a reduction of the effective band gap, being slightly less pronounced in the case of electron withdrawing substituents. The investigated ligands have the optimal geometry for binding to surface Ti atoms, resulting in ring coordination complexes of the catecholate type (binuclear bidentate binding-bridging) thus restoring six-coordinated octahedral geometry of surface Ti atoms. From the absorption measurements (Benesi-Hildebrand plot), the stability constants in methanol/water = 90/10 solutions at pH 2 in the order of 10(3) M-1 have been determined. The binding structures were investigated by using FTIR spectroscopy. Thermal stability of CT-complexes was investigated by using TG/DSC/MS analysis. Quantum chemical calculations on model systems using density functional theory (DFT) were performed to obtain the vibrational frequencies of charge transfer complexes, and the calculated values were compared with the experimental data.
T2  - Physical Chemistry Chemical Physics
T1  - The effect of substituents on the surface modification of anatase nanoparticles with catecholate-type ligands: a combined DFT and experimental study
VL  - 16
IS  - 38
SP  - 20796
EP  - 20805
DO  - 10.1039/c4cp02197e
ER  - 

@article{
author = "Savić, Tatjana D. and Čomor, Mirjana and Nedeljković, Jovan and Veljkovic, Dusan Z. and Zarić, Snežana D. and Rakić, Vesna M. and Janković, Ivana A.",
year = "2014",
abstract = "The surface modification of nanocrystalline TiO2 particles (45 angstrom) with catecholate-type ligands having different electron donating/electron withdrawing substituent groups, specifically 3-methylcatechol, 4-methylcatechol, 3-methoxycatechol, 3,4-dihydroxybenzaldehyde and 4-nitrocatechol, was found to alter the optical properties of nanoparticles in a similar way to catechol. The formation of the inner-sphere charge-transfer (CT) complexes results in a red shift of the semiconductor absorption compared to unmodified nanocrystallites and a reduction of the effective band gap, being slightly less pronounced in the case of electron withdrawing substituents. The investigated ligands have the optimal geometry for binding to surface Ti atoms, resulting in ring coordination complexes of the catecholate type (binuclear bidentate binding-bridging) thus restoring six-coordinated octahedral geometry of surface Ti atoms. From the absorption measurements (Benesi-Hildebrand plot), the stability constants in methanol/water = 90/10 solutions at pH 2 in the order of 10(3) M-1 have been determined. The binding structures were investigated by using FTIR spectroscopy. Thermal stability of CT-complexes was investigated by using TG/DSC/MS analysis. Quantum chemical calculations on model systems using density functional theory (DFT) were performed to obtain the vibrational frequencies of charge transfer complexes, and the calculated values were compared with the experimental data.",
journal = "Physical Chemistry Chemical Physics",
title = "The effect of substituents on the surface modification of anatase nanoparticles with catecholate-type ligands: a combined DFT and experimental study",
volume = "16",
number = "38",
pages = "20796-20805",
doi = "10.1039/c4cp02197e"
}

Savić, T. D., Čomor, M., Nedeljković, J., Veljkovic, D. Z., Zarić, S. D., Rakić, V. M.,& Janković, I. A.. (2014). The effect of substituents on the surface modification of anatase nanoparticles with catecholate-type ligands: a combined DFT and experimental study. in Physical Chemistry Chemical Physics, 16(38), 20796-20805.
https://doi.org/10.1039/c4cp02197e

Savić TD, Čomor M, Nedeljković J, Veljkovic DZ, Zarić SD, Rakić VM, Janković IA. The effect of substituents on the surface modification of anatase nanoparticles with catecholate-type ligands: a combined DFT and experimental study. in Physical Chemistry Chemical Physics. 2014;16(38):20796-20805.
doi:10.1039/c4cp02197e .

Savić, Tatjana D., Čomor, Mirjana, Nedeljković, Jovan, Veljkovic, Dusan Z., Zarić, Snežana D., Rakić, Vesna M., Janković, Ivana A., "The effect of substituents on the surface modification of anatase nanoparticles with catecholate-type ligands: a combined DFT and experimental study" in Physical Chemistry Chemical Physics, 16, no. 38 (2014):20796-20805,
https://doi.org/10.1039/c4cp02197e . .

TY  - JOUR
AU  - Abazović, Nadica
AU  - Radoičić, Marija B.
AU  - Savić, Tatjana D.
AU  - Janković, Ivana A.
AU  - Čomor, Mirjana
PY  - 2013
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/5619
AB  - Gd3+-doped titania nanoparticles have been synthesized via acidic hydrolysis of Gd3+ and Ti4+ organic precursors. The resulting products were characterized by X-ray diffraction, transmition electron microscopy and diffuse reflection spectra. Experimental results indicated that Gd3+-doping makes great impact on the optical properties and photocatalytic activity of the obtained TiO2 nanoparticles. All applied doping concentrations induced enhancement of photoactivity regarding degradation of Rhodamine B, compared to pure TiO2. The inter-band defect states formed as a result of incorporation of Gd3+ ions in the TiO2 matrix are most probably the cause of observed improved photoacatalytic activity and optical properties of the doped TiO2 nanoparticles.
T2  - Digest Journal of Nanomaterials and Biostructures
T1  - Room-Temperature Synthesis and Photocatalytic Activity of Titania Nanoparticles Doped with Gadolinium Ions
VL  - 8
IS  - 2
SP  - 871
EP  - U400
UR  - https://hdl.handle.net/21.15107/rcub_vinar_5619
ER  - 

@article{
author = "Abazović, Nadica and Radoičić, Marija B. and Savić, Tatjana D. and Janković, Ivana A. and Čomor, Mirjana",
year = "2013",
abstract = "Gd3+-doped titania nanoparticles have been synthesized via acidic hydrolysis of Gd3+ and Ti4+ organic precursors. The resulting products were characterized by X-ray diffraction, transmition electron microscopy and diffuse reflection spectra. Experimental results indicated that Gd3+-doping makes great impact on the optical properties and photocatalytic activity of the obtained TiO2 nanoparticles. All applied doping concentrations induced enhancement of photoactivity regarding degradation of Rhodamine B, compared to pure TiO2. The inter-band defect states formed as a result of incorporation of Gd3+ ions in the TiO2 matrix are most probably the cause of observed improved photoacatalytic activity and optical properties of the doped TiO2 nanoparticles.",
journal = "Digest Journal of Nanomaterials and Biostructures",
title = "Room-Temperature Synthesis and Photocatalytic Activity of Titania Nanoparticles Doped with Gadolinium Ions",
volume = "8",
number = "2",
pages = "871-U400",
url = "https://hdl.handle.net/21.15107/rcub_vinar_5619"
}

Abazović, N., Radoičić, M. B., Savić, T. D., Janković, I. A.,& Čomor, M.. (2013). Room-Temperature Synthesis and Photocatalytic Activity of Titania Nanoparticles Doped with Gadolinium Ions. in Digest Journal of Nanomaterials and Biostructures, 8(2), 871-U400.
https://hdl.handle.net/21.15107/rcub_vinar_5619

Abazović N, Radoičić MB, Savić TD, Janković IA, Čomor M. Room-Temperature Synthesis and Photocatalytic Activity of Titania Nanoparticles Doped with Gadolinium Ions. in Digest Journal of Nanomaterials and Biostructures. 2013;8(2):871-U400.
https://hdl.handle.net/21.15107/rcub_vinar_5619 .

Abazović, Nadica, Radoičić, Marija B., Savić, Tatjana D., Janković, Ivana A., Čomor, Mirjana, "Room-Temperature Synthesis and Photocatalytic Activity of Titania Nanoparticles Doped with Gadolinium Ions" in Digest Journal of Nanomaterials and Biostructures, 8, no. 2 (2013):871-U400,
https://hdl.handle.net/21.15107/rcub_vinar_5619 .

TY  - JOUR
AU  - Savić, Tatjana D.
AU  - Validžić, Ivana Lj.
AU  - Novaković, Tatjana
AU  - Vuković, Zorica M.
AU  - Čomor, Mirjana
PY  - 2013
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/5642
AB  - ZnO/ZnWO4 composite rod-like nanoparticles were synthesized by low-temperature soft solution method at 95 A degrees C with different reaction times (1-120 h), in the presence of non-ionic copolymer surfactant Pluronic F68. Obtained nanoparticles had diameters in the range around 10 nm and length of 30 nm. Optical properties such as reflection and room temperature photoluminescence of obtained samples showed strong dependence on their crystallinity and composition. Photocatalytic activity of ZnO/ZnWO4 nanopowders was checked using photodegradation of selected dyes as model system. Obtained results were correlated with specific surface area, particle sizes, crystallinity and ZnO/ZnWO4 ratio of the samples. As crystallinity of ZnWO4 component in the ZnO/ZnWO4 increase, photocatalytic activity also increases. The main findings can be explained by charge transfer reactions that follow light absorption by ZnO and ZnWO4 in nanocomposite.
T2  - Journal of Cluster Science
T1  - A Synergy of ZnO and ZnWO4 in Composite Nanostructures Deduced from Optical Properties and Photocatalysis
VL  - 24
IS  - 3
SP  - 679
EP  - 688
DO  - 10.1007/s10876-013-0562-7
ER  - 

@article{
author = "Savić, Tatjana D. and Validžić, Ivana Lj. and Novaković, Tatjana and Vuković, Zorica M. and Čomor, Mirjana",
year = "2013",
abstract = "ZnO/ZnWO4 composite rod-like nanoparticles were synthesized by low-temperature soft solution method at 95 A degrees C with different reaction times (1-120 h), in the presence of non-ionic copolymer surfactant Pluronic F68. Obtained nanoparticles had diameters in the range around 10 nm and length of 30 nm. Optical properties such as reflection and room temperature photoluminescence of obtained samples showed strong dependence on their crystallinity and composition. Photocatalytic activity of ZnO/ZnWO4 nanopowders was checked using photodegradation of selected dyes as model system. Obtained results were correlated with specific surface area, particle sizes, crystallinity and ZnO/ZnWO4 ratio of the samples. As crystallinity of ZnWO4 component in the ZnO/ZnWO4 increase, photocatalytic activity also increases. The main findings can be explained by charge transfer reactions that follow light absorption by ZnO and ZnWO4 in nanocomposite.",
journal = "Journal of Cluster Science",
title = "A Synergy of ZnO and ZnWO4 in Composite Nanostructures Deduced from Optical Properties and Photocatalysis",
volume = "24",
number = "3",
pages = "679-688",
doi = "10.1007/s10876-013-0562-7"
}

Savić, T. D., Validžić, I. Lj., Novaković, T., Vuković, Z. M.,& Čomor, M.. (2013). A Synergy of ZnO and ZnWO4 in Composite Nanostructures Deduced from Optical Properties and Photocatalysis. in Journal of Cluster Science, 24(3), 679-688.
https://doi.org/10.1007/s10876-013-0562-7

Savić TD, Validžić IL, Novaković T, Vuković ZM, Čomor M. A Synergy of ZnO and ZnWO4 in Composite Nanostructures Deduced from Optical Properties and Photocatalysis. in Journal of Cluster Science. 2013;24(3):679-688.
doi:10.1007/s10876-013-0562-7 .

Savić, Tatjana D., Validžić, Ivana Lj., Novaković, Tatjana, Vuković, Zorica M., Čomor, Mirjana, "A Synergy of ZnO and ZnWO4 in Composite Nanostructures Deduced from Optical Properties and Photocatalysis" in Journal of Cluster Science, 24, no. 3 (2013):679-688,
https://doi.org/10.1007/s10876-013-0562-7 . .

TY  - JOUR
AU  - Radoičić, Marija B.
AU  - Janković, Ivana A.
AU  - Despotović, Vesna N.
AU  - Šojić, Daniela V.
AU  - Savić, Tatjana D.
AU  - Šaponjić, Zoran
AU  - Abramović, Biljana F.
AU  - Čomor, Mirjana
PY  - 2013
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/5511
AB  - A study of photocatalytic activity of bare as prepared, bare aged and dopamine surface modified colloidal TiO2 nanoparticles was obtained following degradation reaction of herbicide RS-2-(4-chloro-o-tolyloxy)propionic acid under UV light irradiation. Results showed that the most active photocatalyst is bare aged TiO2 and the least active are dopamine modified nanoparticles. Results are discussed in the light of surface structure of TiO2 nanoparticles. The study of surface modification of TiO2 nanoparticles (4.5 nm, TiO2 NPs) with dopamine was also performed. The formation of inner-sphere charge-transfer complexes results in red shift of semiconductor absorption threshold (600 nm), compared to bare TiO2 NPs (380 nm). Effective band gap energy of 3.2 eV for bare TiO2 NPs is reduced to 2.1 eV for TiO2/dopamine charge transfer complexes. The binding structure was investigated by UV-vis and FTIR spectroscopy. The obtained optimal geometry for binding of dopamine to surface Ti atoms was binuclear bidentate-bridging. From the Benesi-Hildebrand plot, stability constant of the order 10(3) M-1 has been determined. (C) 2013 Elsevier B.V. All rights reserved.
T2  - Applied Catalysis. B: Environmental
T1  - The role of surface defect sites of titania nanoparticles in the photocatalysis: Aging and modification
VL  - 138
SP  - 122
EP  - 127
DO  - 10.1016/j.apcatb.2013.02.032
ER  - 

@article{
author = "Radoičić, Marija B. and Janković, Ivana A. and Despotović, Vesna N. and Šojić, Daniela V. and Savić, Tatjana D. and Šaponjić, Zoran and Abramović, Biljana F. and Čomor, Mirjana",
year = "2013",
abstract = "A study of photocatalytic activity of bare as prepared, bare aged and dopamine surface modified colloidal TiO2 nanoparticles was obtained following degradation reaction of herbicide RS-2-(4-chloro-o-tolyloxy)propionic acid under UV light irradiation. Results showed that the most active photocatalyst is bare aged TiO2 and the least active are dopamine modified nanoparticles. Results are discussed in the light of surface structure of TiO2 nanoparticles. The study of surface modification of TiO2 nanoparticles (4.5 nm, TiO2 NPs) with dopamine was also performed. The formation of inner-sphere charge-transfer complexes results in red shift of semiconductor absorption threshold (600 nm), compared to bare TiO2 NPs (380 nm). Effective band gap energy of 3.2 eV for bare TiO2 NPs is reduced to 2.1 eV for TiO2/dopamine charge transfer complexes. The binding structure was investigated by UV-vis and FTIR spectroscopy. The obtained optimal geometry for binding of dopamine to surface Ti atoms was binuclear bidentate-bridging. From the Benesi-Hildebrand plot, stability constant of the order 10(3) M-1 has been determined. (C) 2013 Elsevier B.V. All rights reserved.",
journal = "Applied Catalysis. B: Environmental",
title = "The role of surface defect sites of titania nanoparticles in the photocatalysis: Aging and modification",
volume = "138",
pages = "122-127",
doi = "10.1016/j.apcatb.2013.02.032"
}

Radoičić, M. B., Janković, I. A., Despotović, V. N., Šojić, D. V., Savić, T. D., Šaponjić, Z., Abramović, B. F.,& Čomor, M.. (2013). The role of surface defect sites of titania nanoparticles in the photocatalysis: Aging and modification. in Applied Catalysis. B: Environmental, 138, 122-127.
https://doi.org/10.1016/j.apcatb.2013.02.032

Radoičić MB, Janković IA, Despotović VN, Šojić DV, Savić TD, Šaponjić Z, Abramović BF, Čomor M. The role of surface defect sites of titania nanoparticles in the photocatalysis: Aging and modification. in Applied Catalysis. B: Environmental. 2013;138:122-127.
doi:10.1016/j.apcatb.2013.02.032 .

Radoičić, Marija B., Janković, Ivana A., Despotović, Vesna N., Šojić, Daniela V., Savić, Tatjana D., Šaponjić, Zoran, Abramović, Biljana F., Čomor, Mirjana, "The role of surface defect sites of titania nanoparticles in the photocatalysis: Aging and modification" in Applied Catalysis. B: Environmental, 138 (2013):122-127,
https://doi.org/10.1016/j.apcatb.2013.02.032 . .

TY  - JOUR
AU  - Savić, Tatjana D.
AU  - Šaponjić, Zoran
AU  - Čomor, Mirjana
AU  - Nedeljković, Jovan
AU  - Dramićanin, Miroslav
AU  - Nikolić, Marko G.
AU  - Veljkovic, Dusan Z.
AU  - Zarić, Snežana D.
AU  - Janković, Ivana A.
PY  - 2013
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/5601
AB  - The surface modification of nanocrystalline TiO2 particles (45 angstrom) with salicylate-type ligands consisting of an extended aromatic ring system, specifically 3-hydroxy-2-naphthoic acid, 3,5-dihydroxy-2-naphthoic acid and 3,7-dihydroxy-2-naphthoic acid, was found to alter the optical properties of nanoparticles in a similar way to salicylic acid. The formation of the inner-sphere charge-transfer (CT) complexes results in a red shift of the semiconductor absorption compared to unmodified nanocrystallites and a reduction in the band gap upon the increase in the electron delocalization when including an additional ring. The investigated ligands have the optimal geometry for binding to surface Ti atoms, resulting in ring coordination complexes of a salicylate-type (binuclear bidentate binding-bridging) thus restoring the six-coordinated octahedral geometry of surface Ti atoms. From both absorption measurements in methanol/water = 90/10 solutions and steady-state quenching measurements of modifier fluorescence upon binding to TiO2 in aqueous solutions, stability constants in the order of 10(3) M-1 have been determined at pH 2 and pH 3. Fluorescence lifetime measurements, in the presence and absence of colloidal TiO2 nanoparticles, indicated that the fluorescence quenching process is primarily static quenching, thus proving the formation of a nonfluorescent CT complex. The binding structures were investigated by using FTIR spectroscopy. Quantum chemical calculations on model systems using density functional theory (DFT) were performed to obtain the vibrational frequencies of charge transfer complexes, and the calculated values were then compared with the experimental data.
T2  - Nanoscale
T1  - Surface modification of anatase nanoparticles with fused ring salicylate-type ligands (3-hydroxy-2-naphthoic acids): a combined DFT and experimental study of optical properties
VL  - 5
IS  - 16
SP  - 7601
EP  - 7612
DO  - 10.1039/c3nr01277h
ER  - 

@article{
author = "Savić, Tatjana D. and Šaponjić, Zoran and Čomor, Mirjana and Nedeljković, Jovan and Dramićanin, Miroslav and Nikolić, Marko G. and Veljkovic, Dusan Z. and Zarić, Snežana D. and Janković, Ivana A.",
year = "2013",
abstract = "The surface modification of nanocrystalline TiO2 particles (45 angstrom) with salicylate-type ligands consisting of an extended aromatic ring system, specifically 3-hydroxy-2-naphthoic acid, 3,5-dihydroxy-2-naphthoic acid and 3,7-dihydroxy-2-naphthoic acid, was found to alter the optical properties of nanoparticles in a similar way to salicylic acid. The formation of the inner-sphere charge-transfer (CT) complexes results in a red shift of the semiconductor absorption compared to unmodified nanocrystallites and a reduction in the band gap upon the increase in the electron delocalization when including an additional ring. The investigated ligands have the optimal geometry for binding to surface Ti atoms, resulting in ring coordination complexes of a salicylate-type (binuclear bidentate binding-bridging) thus restoring the six-coordinated octahedral geometry of surface Ti atoms. From both absorption measurements in methanol/water = 90/10 solutions and steady-state quenching measurements of modifier fluorescence upon binding to TiO2 in aqueous solutions, stability constants in the order of 10(3) M-1 have been determined at pH 2 and pH 3. Fluorescence lifetime measurements, in the presence and absence of colloidal TiO2 nanoparticles, indicated that the fluorescence quenching process is primarily static quenching, thus proving the formation of a nonfluorescent CT complex. The binding structures were investigated by using FTIR spectroscopy. Quantum chemical calculations on model systems using density functional theory (DFT) were performed to obtain the vibrational frequencies of charge transfer complexes, and the calculated values were then compared with the experimental data.",
journal = "Nanoscale",
title = "Surface modification of anatase nanoparticles with fused ring salicylate-type ligands (3-hydroxy-2-naphthoic acids): a combined DFT and experimental study of optical properties",
volume = "5",
number = "16",
pages = "7601-7612",
doi = "10.1039/c3nr01277h"
}

Savić, T. D., Šaponjić, Z., Čomor, M., Nedeljković, J., Dramićanin, M., Nikolić, M. G., Veljkovic, D. Z., Zarić, S. D.,& Janković, I. A.. (2013). Surface modification of anatase nanoparticles with fused ring salicylate-type ligands (3-hydroxy-2-naphthoic acids): a combined DFT and experimental study of optical properties. in Nanoscale, 5(16), 7601-7612.
https://doi.org/10.1039/c3nr01277h

Savić TD, Šaponjić Z, Čomor M, Nedeljković J, Dramićanin M, Nikolić MG, Veljkovic DZ, Zarić SD, Janković IA. Surface modification of anatase nanoparticles with fused ring salicylate-type ligands (3-hydroxy-2-naphthoic acids): a combined DFT and experimental study of optical properties. in Nanoscale. 2013;5(16):7601-7612.
doi:10.1039/c3nr01277h .

Savić, Tatjana D., Šaponjić, Zoran, Čomor, Mirjana, Nedeljković, Jovan, Dramićanin, Miroslav, Nikolić, Marko G., Veljkovic, Dusan Z., Zarić, Snežana D., Janković, Ivana A., "Surface modification of anatase nanoparticles with fused ring salicylate-type ligands (3-hydroxy-2-naphthoic acids): a combined DFT and experimental study of optical properties" in Nanoscale, 5, no. 16 (2013):7601-7612,
https://doi.org/10.1039/c3nr01277h . .

TY  - CONF
AU  - Savić, Tatjana D.
AU  - Validžić, Ivana Lj.
AU  - Čomor, Mirjana
PY  - 2012
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/9313
AB  - ZnO/ZnWO4 composite rod-like nanoparticles were synthesized by lowtemperature soft solution method at 95º C with different reaction times (1-120
hours), in the presence of non-ionic copolymer surfactant Pluronic F68. Optical
properties such as reflection and room temperature photoluminescence of obtained
samples showed strong dependence on their crystallinity and composition.
PB  - Society of Physical Chemists of Serbia
C3  - Physical chemistry 2012 : 11th international conference on fundamental and applied aspects of physical chemistry
T1  - Optical properties of ZnO/Zn/WO4 composite nanoparticles
VL  - 1
SP  - 465
EP  - 467
UR  - https://hdl.handle.net/21.15107/rcub_vinar_9313
ER  - 

@conference{
author = "Savić, Tatjana D. and Validžić, Ivana Lj. and Čomor, Mirjana",
year = "2012",
abstract = "ZnO/ZnWO4 composite rod-like nanoparticles were synthesized by lowtemperature soft solution method at 95º C with different reaction times (1-120
hours), in the presence of non-ionic copolymer surfactant Pluronic F68. Optical
properties such as reflection and room temperature photoluminescence of obtained
samples showed strong dependence on their crystallinity and composition.",
publisher = "Society of Physical Chemists of Serbia",
journal = "Physical chemistry 2012 : 11th international conference on fundamental and applied aspects of physical chemistry",
title = "Optical properties of ZnO/Zn/WO4 composite nanoparticles",
volume = "1",
pages = "465-467",
url = "https://hdl.handle.net/21.15107/rcub_vinar_9313"
}

Savić, T. D., Validžić, I. Lj.,& Čomor, M.. (2012). Optical properties of ZnO/Zn/WO4 composite nanoparticles. in Physical chemistry 2012 : 11th international conference on fundamental and applied aspects of physical chemistry
Society of Physical Chemists of Serbia., 1, 465-467.
https://hdl.handle.net/21.15107/rcub_vinar_9313

Savić TD, Validžić IL, Čomor M. Optical properties of ZnO/Zn/WO4 composite nanoparticles. in Physical chemistry 2012 : 11th international conference on fundamental and applied aspects of physical chemistry. 2012;1:465-467.
https://hdl.handle.net/21.15107/rcub_vinar_9313 .

Savić, Tatjana D., Validžić, Ivana Lj., Čomor, Mirjana, "Optical properties of ZnO/Zn/WO4 composite nanoparticles" in Physical chemistry 2012 : 11th international conference on fundamental and applied aspects of physical chemistry, 1 (2012):465-467,
https://hdl.handle.net/21.15107/rcub_vinar_9313 .

TY  - JOUR
AU  - Validžić, Ivana Lj.
AU  - Savić, Tatjana D.
AU  - Krsmanović, Radenka
AU  - Jovanović, Dragana J.
AU  - Novaković, Mirjana M.
AU  - Popović, Maja
AU  - Čomor, Mirjana
PY  - 2012
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/4857
AB  - Zinc oxide (ZnO)/zinc tungstate (ZnWO4) rod-like nanoparticles with diameters in the range of 6-11 nm and length of about 30 nm were synthesized by a low temperature soft solution method at 95-C in the presence of non-ionic copolymer surfactant. It was found that their crystallinity was enhanced with the increase of heating time from 1 h up to 120h. The photoluminescence (PL) measurements showed very strong, narrow UV band peaked at 3.30 eV and a broad visible band peaking at 2.71 eV with a shoulder at about 2.53 eV, for lambda(exc) LT 300 nm. Quite large variations in the intensities of the two PL bands were observed for different excitation wavelengths. The intensity of the main visible band decreases with decreasing excitation energy and disappears when samples are excited lambda = 320 nm (E-exc = 3.875 eV). We found that observed optical properties originate from ZnO phase. UV band gap PL had high intensity for all applied excitations, probably induced by ZnWO4 phase presence on the surface. In addition, two values were found for direct band-gap energy of ZnO/ZnWO4 rod-like nanoparticles 3.62 and 3.21 eV, determined from reflectance spectrum. The photocatalytic behaviour of ZnO is strongly dependent on the formation of ZnWO4 phase, of the obtained rod-like nanoparticles. (C) 2012 Elsevier B.V. All rights reserved.
PB  - Elsevier
T2  - Materials Science and Engineering. B: Advanced Functional Solid-State Materials
T1  - Synthesis, strong room-temperature PL and photocatalytic activity of ZnO/ZnWO4 rod-like nanoparticles
VL  - 177
IS  - 9
SP  - 645
EP  - 651
DO  - 10.1016/j.mseb.2012.03.044
ER  - 

@article{
author = "Validžić, Ivana Lj. and Savić, Tatjana D. and Krsmanović, Radenka and Jovanović, Dragana J. and Novaković, Mirjana M. and Popović, Maja and Čomor, Mirjana",
year = "2012",
abstract = "Zinc oxide (ZnO)/zinc tungstate (ZnWO4) rod-like nanoparticles with diameters in the range of 6-11 nm and length of about 30 nm were synthesized by a low temperature soft solution method at 95-C in the presence of non-ionic copolymer surfactant. It was found that their crystallinity was enhanced with the increase of heating time from 1 h up to 120h. The photoluminescence (PL) measurements showed very strong, narrow UV band peaked at 3.30 eV and a broad visible band peaking at 2.71 eV with a shoulder at about 2.53 eV, for lambda(exc) LT 300 nm. Quite large variations in the intensities of the two PL bands were observed for different excitation wavelengths. The intensity of the main visible band decreases with decreasing excitation energy and disappears when samples are excited lambda = 320 nm (E-exc = 3.875 eV). We found that observed optical properties originate from ZnO phase. UV band gap PL had high intensity for all applied excitations, probably induced by ZnWO4 phase presence on the surface. In addition, two values were found for direct band-gap energy of ZnO/ZnWO4 rod-like nanoparticles 3.62 and 3.21 eV, determined from reflectance spectrum. The photocatalytic behaviour of ZnO is strongly dependent on the formation of ZnWO4 phase, of the obtained rod-like nanoparticles. (C) 2012 Elsevier B.V. All rights reserved.",
publisher = "Elsevier",
journal = "Materials Science and Engineering. B: Advanced Functional Solid-State Materials",
title = "Synthesis, strong room-temperature PL and photocatalytic activity of ZnO/ZnWO4 rod-like nanoparticles",
volume = "177",
number = "9",
pages = "645-651",
doi = "10.1016/j.mseb.2012.03.044"
}

Validžić, I. Lj., Savić, T. D., Krsmanović, R., Jovanović, D. J., Novaković, M. M., Popović, M.,& Čomor, M.. (2012). Synthesis, strong room-temperature PL and photocatalytic activity of ZnO/ZnWO4 rod-like nanoparticles. in Materials Science and Engineering. B: Advanced Functional Solid-State Materials
Elsevier., 177(9), 645-651.
https://doi.org/10.1016/j.mseb.2012.03.044

Validžić IL, Savić TD, Krsmanović R, Jovanović DJ, Novaković MM, Popović M, Čomor M. Synthesis, strong room-temperature PL and photocatalytic activity of ZnO/ZnWO4 rod-like nanoparticles. in Materials Science and Engineering. B: Advanced Functional Solid-State Materials. 2012;177(9):645-651.
doi:10.1016/j.mseb.2012.03.044 .

Validžić, Ivana Lj., Savić, Tatjana D., Krsmanović, Radenka, Jovanović, Dragana J., Novaković, Mirjana M., Popović, Maja, Čomor, Mirjana, "Synthesis, strong room-temperature PL and photocatalytic activity of ZnO/ZnWO4 rod-like nanoparticles" in Materials Science and Engineering. B: Advanced Functional Solid-State Materials, 177, no. 9 (2012):645-651,
https://doi.org/10.1016/j.mseb.2012.03.044 . .

TY  - JOUR
AU  - Savić, Tatjana D.
AU  - Janković, Ivana A.
AU  - Šaponjić, Zoran
AU  - Čomor, Mirjana
AU  - Veljkovic, Dusan Z.
AU  - Zarić, Snežana D.
AU  - Nedeljković, Jovan
PY  - 2012
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/4698
AB  - Surface modification of nanocrystalline TiO2 particles (45 angstrom) with catecholate-type ligands consisting of an extended aromatic ring system, i.e., 2,3-dihydroxynaphthalene and anthrarobin, was found to alter the optical properties of the nanoparticles in a similar way to modification with catechol. The formation of inner-sphere charge-transfer (CT) complexes results in a red shift of the semiconductor absorption compared to unmodified nanocrystallites and the reduction of the band gap upon the increase of the electron delocalization on the inclusion of additional rings. The binding structures were investigated by FTIR spectroscopy. The investigated ligands have the optimal geometry for binding to surface Ti atoms, resulting in ring coordination complexes of catecholate type (binuclear bidentate binding-bridging) thus restoring the six-coordinated octahedral geometry of surface Ti atoms. From the Benesi-Hildebrand plot, stability constants in methanol/water = 90/10 solutions at pH 2 of the order 10(3) M-1 have been determined. Quantum chemical calculations on model systems using density functional theory (DFT) were performed to obtain vibrational frequencies of charge transfer complexes, and the calculated values were compared with the experimental data.
T2  - Nanoscale
T1  - Surface modification of anatase nanoparticles with fused ring catecholate type ligands: a combined DFT and experimental study of optical properties
VL  - 4
IS  - 5
SP  - 1612
EP  - 1619
DO  - 10.1039/c2nr11501h
ER  - 

@article{
author = "Savić, Tatjana D. and Janković, Ivana A. and Šaponjić, Zoran and Čomor, Mirjana and Veljkovic, Dusan Z. and Zarić, Snežana D. and Nedeljković, Jovan",
year = "2012",
abstract = "Surface modification of nanocrystalline TiO2 particles (45 angstrom) with catecholate-type ligands consisting of an extended aromatic ring system, i.e., 2,3-dihydroxynaphthalene and anthrarobin, was found to alter the optical properties of the nanoparticles in a similar way to modification with catechol. The formation of inner-sphere charge-transfer (CT) complexes results in a red shift of the semiconductor absorption compared to unmodified nanocrystallites and the reduction of the band gap upon the increase of the electron delocalization on the inclusion of additional rings. The binding structures were investigated by FTIR spectroscopy. The investigated ligands have the optimal geometry for binding to surface Ti atoms, resulting in ring coordination complexes of catecholate type (binuclear bidentate binding-bridging) thus restoring the six-coordinated octahedral geometry of surface Ti atoms. From the Benesi-Hildebrand plot, stability constants in methanol/water = 90/10 solutions at pH 2 of the order 10(3) M-1 have been determined. Quantum chemical calculations on model systems using density functional theory (DFT) were performed to obtain vibrational frequencies of charge transfer complexes, and the calculated values were compared with the experimental data.",
journal = "Nanoscale",
title = "Surface modification of anatase nanoparticles with fused ring catecholate type ligands: a combined DFT and experimental study of optical properties",
volume = "4",
number = "5",
pages = "1612-1619",
doi = "10.1039/c2nr11501h"
}

Savić, T. D., Janković, I. A., Šaponjić, Z., Čomor, M., Veljkovic, D. Z., Zarić, S. D.,& Nedeljković, J.. (2012). Surface modification of anatase nanoparticles with fused ring catecholate type ligands: a combined DFT and experimental study of optical properties. in Nanoscale, 4(5), 1612-1619.
https://doi.org/10.1039/c2nr11501h

Savić TD, Janković IA, Šaponjić Z, Čomor M, Veljkovic DZ, Zarić SD, Nedeljković J. Surface modification of anatase nanoparticles with fused ring catecholate type ligands: a combined DFT and experimental study of optical properties. in Nanoscale. 2012;4(5):1612-1619.
doi:10.1039/c2nr11501h .

Savić, Tatjana D., Janković, Ivana A., Šaponjić, Zoran, Čomor, Mirjana, Veljkovic, Dusan Z., Zarić, Snežana D., Nedeljković, Jovan, "Surface modification of anatase nanoparticles with fused ring catecholate type ligands: a combined DFT and experimental study of optical properties" in Nanoscale, 4, no. 5 (2012):1612-1619,
https://doi.org/10.1039/c2nr11501h . .