TY  - JOUR
AU  - Bjelajac, Anđelika
AU  - Petrović, Rada
AU  - Popović, Maja
AU  - Rakočević, Zlatko Lj.
AU  - Socol, Gabriel
AU  - Mihailescu, Ion N.
AU  - Janaćković, Đorđe T.
PY  - 2019
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/8589
AB  - The ∼60 nm wide and ∼2 μm long TiO2 nanotubes were obtained by anodization of Ti films sputtered on F-doped tin oxide glass. For N-doping the samples were annealed in ammonia atmosphere. The effect of pre- and post-annealing in air on the nature and amount of incorporated N was studied by X-ray photoelectron spectroscopy. By measuring the absorption spectra of the obtained samples and interpreting the corresponding Tauc plots it was shown that the sample annealed just in ammonia showed the highest visible light absorption even after sputtering cleaning and a decrease of N amount from 3.8% to 1%. Pre and/or post annealing in air led to smaller amount of incorporated N, that caused less pronounced absorption enhancement and smaller band gap narrowing compared to the sample annealed only in ammonia. By fitting of N 1 s line, the contribution that was assigned to substitutional N was detected only in the samples that did not sustained post-annealing. The study showed that post-annealing in air might lead to partial conversion of N atoms in TiO2 to oxidized nitrogen species that are easily removed with sputtering. It is also possible that substitutional nitrogen was suppressed by oxygen from air to move to interstitial site. Weakly bonded NOx surface species, which are cleaned away by sputtering, can be removed by post-annealing in air. Those surface species could act as sensitizers and when their amounts are reduced, the core absorption properties, as a result of interstitial incorporation of N in TiO2 structure, were revealed. Much lower visible light sensitization was achieved in the case of pre-annealed sample in comparison to sample without pre-annealing, regardless the same quantity and type of incorporated nitrogen.
T2  - Thin Solid Films
T1  - Doping of TiO2 nanotubes with nitrogen by annealing in ammonia for visible light activation: Influence of pre- and post-annealing in air
VL  - 692
SP  - 137598
DO  - 10.1016/j.tsf.2019.137598
ER  - 

@article{
author = "Bjelajac, Anđelika and Petrović, Rada and Popović, Maja and Rakočević, Zlatko Lj. and Socol, Gabriel and Mihailescu, Ion N. and Janaćković, Đorđe T.",
year = "2019",
abstract = "The ∼60 nm wide and ∼2 μm long TiO2 nanotubes were obtained by anodization of Ti films sputtered on F-doped tin oxide glass. For N-doping the samples were annealed in ammonia atmosphere. The effect of pre- and post-annealing in air on the nature and amount of incorporated N was studied by X-ray photoelectron spectroscopy. By measuring the absorption spectra of the obtained samples and interpreting the corresponding Tauc plots it was shown that the sample annealed just in ammonia showed the highest visible light absorption even after sputtering cleaning and a decrease of N amount from 3.8% to 1%. Pre and/or post annealing in air led to smaller amount of incorporated N, that caused less pronounced absorption enhancement and smaller band gap narrowing compared to the sample annealed only in ammonia. By fitting of N 1 s line, the contribution that was assigned to substitutional N was detected only in the samples that did not sustained post-annealing. The study showed that post-annealing in air might lead to partial conversion of N atoms in TiO2 to oxidized nitrogen species that are easily removed with sputtering. It is also possible that substitutional nitrogen was suppressed by oxygen from air to move to interstitial site. Weakly bonded NOx surface species, which are cleaned away by sputtering, can be removed by post-annealing in air. Those surface species could act as sensitizers and when their amounts are reduced, the core absorption properties, as a result of interstitial incorporation of N in TiO2 structure, were revealed. Much lower visible light sensitization was achieved in the case of pre-annealed sample in comparison to sample without pre-annealing, regardless the same quantity and type of incorporated nitrogen.",
journal = "Thin Solid Films",
title = "Doping of TiO2 nanotubes with nitrogen by annealing in ammonia for visible light activation: Influence of pre- and post-annealing in air",
volume = "692",
pages = "137598",
doi = "10.1016/j.tsf.2019.137598"
}

Bjelajac, A., Petrović, R., Popović, M., Rakočević, Z. Lj., Socol, G., Mihailescu, I. N.,& Janaćković, Đ. T.. (2019). Doping of TiO2 nanotubes with nitrogen by annealing in ammonia for visible light activation: Influence of pre- and post-annealing in air. in Thin Solid Films, 692, 137598.
https://doi.org/10.1016/j.tsf.2019.137598

Bjelajac A, Petrović R, Popović M, Rakočević ZL, Socol G, Mihailescu IN, Janaćković ĐT. Doping of TiO2 nanotubes with nitrogen by annealing in ammonia for visible light activation: Influence of pre- and post-annealing in air. in Thin Solid Films. 2019;692:137598.
doi:10.1016/j.tsf.2019.137598 .

Bjelajac, Anđelika, Petrović, Rada, Popović, Maja, Rakočević, Zlatko Lj., Socol, Gabriel, Mihailescu, Ion N., Janaćković, Đorđe T., "Doping of TiO2 nanotubes with nitrogen by annealing in ammonia for visible light activation: Influence of pre- and post-annealing in air" in Thin Solid Films, 692 (2019):137598,
https://doi.org/10.1016/j.tsf.2019.137598 . .

TY  - JOUR
AU  - Petrović, Suzana
AU  - Gaković, Biljana M.
AU  - Panjan, Peter
AU  - Kovač, Janez
AU  - Lazović, Vladimir M.
AU  - Ristoscu, Carmen
AU  - Negut, Irina
AU  - Mihailescu, Ion N.
PY  - 2018
UR  - http://link.springer.com/10.1007/s11082-018-1475-3
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/7686
AB  - The oxidation behaviour and morphological modification of CrN/(Cr,V)N coatings on Si wafers were studied after UV nanosecond laser (wavelength 248 nm, pulse duration 25 ns) processing in ambient air. The evolution of the surface composition and microstructure with the number of accumulated/subsequent pulses was systematically analysed depending on the initial content of vanadium in the as-deposited coatings. Irradiation of CrN/(Cr,V)N coatings with different content of vanadium was carried out at a fluence of 0.17 J cm−2with different number of pulses. The concentration of metallic components was fairly homogeneous distributed throughout the sample. However, on surface and in sub-surface regions the contents of Cr and V are diminished due to laser-induced oxidation. The composition and thickness of forming oxides mixture, Cr2O3and V2O5, are depending on the number of applied laser pulses and the initial vanadium content. The asymmetric progress of surface morphology is characterized by the formation of grainy structures at peripheries and the appearance of cracks and irregular closed shapes in the centre of the irradiation area.
T2  - Optical and Quantum Electronics
T1  - Oxidation behaviour of composite CrN/(Cr,V)N coatings with different contents of vanadium induced by UV nanosecond laser pulses
VL  - 50
IS  - 5
SP  - 208
DO  - 10.1007/s11082-018-1475-3
ER  - 

@article{
author = "Petrović, Suzana and Gaković, Biljana M. and Panjan, Peter and Kovač, Janez and Lazović, Vladimir M. and Ristoscu, Carmen and Negut, Irina and Mihailescu, Ion N.",
year = "2018",
abstract = "The oxidation behaviour and morphological modification of CrN/(Cr,V)N coatings on Si wafers were studied after UV nanosecond laser (wavelength 248 nm, pulse duration 25 ns) processing in ambient air. The evolution of the surface composition and microstructure with the number of accumulated/subsequent pulses was systematically analysed depending on the initial content of vanadium in the as-deposited coatings. Irradiation of CrN/(Cr,V)N coatings with different content of vanadium was carried out at a fluence of 0.17 J cm−2with different number of pulses. The concentration of metallic components was fairly homogeneous distributed throughout the sample. However, on surface and in sub-surface regions the contents of Cr and V are diminished due to laser-induced oxidation. The composition and thickness of forming oxides mixture, Cr2O3and V2O5, are depending on the number of applied laser pulses and the initial vanadium content. The asymmetric progress of surface morphology is characterized by the formation of grainy structures at peripheries and the appearance of cracks and irregular closed shapes in the centre of the irradiation area.",
journal = "Optical and Quantum Electronics",
title = "Oxidation behaviour of composite CrN/(Cr,V)N coatings with different contents of vanadium induced by UV nanosecond laser pulses",
volume = "50",
number = "5",
pages = "208",
doi = "10.1007/s11082-018-1475-3"
}

Petrović, S., Gaković, B. M., Panjan, P., Kovač, J., Lazović, V. M., Ristoscu, C., Negut, I.,& Mihailescu, I. N.. (2018). Oxidation behaviour of composite CrN/(Cr,V)N coatings with different contents of vanadium induced by UV nanosecond laser pulses. in Optical and Quantum Electronics, 50(5), 208.
https://doi.org/10.1007/s11082-018-1475-3

Petrović S, Gaković BM, Panjan P, Kovač J, Lazović VM, Ristoscu C, Negut I, Mihailescu IN. Oxidation behaviour of composite CrN/(Cr,V)N coatings with different contents of vanadium induced by UV nanosecond laser pulses. in Optical and Quantum Electronics. 2018;50(5):208.
doi:10.1007/s11082-018-1475-3 .

Petrović, Suzana, Gaković, Biljana M., Panjan, Peter, Kovač, Janez, Lazović, Vladimir M., Ristoscu, Carmen, Negut, Irina, Mihailescu, Ion N., "Oxidation behaviour of composite CrN/(Cr,V)N coatings with different contents of vanadium induced by UV nanosecond laser pulses" in Optical and Quantum Electronics, 50, no. 5 (2018):208,
https://doi.org/10.1007/s11082-018-1475-3 . .

TY  - JOUR
AU  - Petrović, Suzana
AU  - Gaković, Biljana M.
AU  - Zamfirescu, M.
AU  - Radu, C.
AU  - Peruško, Davor
AU  - Radak, Bojan
AU  - Ristoscu, Carmen
AU  - Zdravković, Slobodan
AU  - Luculescu, C. L.
AU  - Mihailescu, Ion N.
PY  - 2017
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/7164
AB  - Modification of single and complex nickel-palladium samples by laser processing in the femtosecond time domain was studied. The samples were processed by focused Ti:Sapphire laser beam (Clark CPA-2101) with 775 nm laser wavelength, 2 kHz repetition rate, 200 fs pulse duration. The laser-induced morphological modifications have shown dependence on the applied fluences and number of laser pulses. The formed surface nanostructures on the single NiPd/Si and multilayer 5x(Ni/Pd)/Si systems are compared with individual Ni and Pd thin films. 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 number of pulses (less than 10 pulses) and low pulse energies range (not over 1.7 mu J), the two types of laser-induced periodic surface structure (LIPSS) can be observed: low and high spatial frequency LIPSS (HSFL and LSFL). For all samples, the measured LSFL periods were 720 nm for the ripples created solely on thin film surfaces during the single pulse action. In the case of the multi-pulse irradiation, the periodicities of created LSFLs on the all investigated thin films have shown tendency to reduction with increasing of pulse energies. (C) 2016 Elsevier B.V. All rights reserved.
T2  - Applied Surface Science
T1  - Femtosecond laser processing of NiPd single and 5x(Ni/Pd) multilayer thin films
VL  - 417
SP  - 16
EP  - 22
DO  - 10.1016/j.apsusc.2016.12.142
ER  - 

@article{
author = "Petrović, Suzana and Gaković, Biljana M. and Zamfirescu, M. and Radu, C. and Peruško, Davor and Radak, Bojan and Ristoscu, Carmen and Zdravković, Slobodan and Luculescu, C. L. and Mihailescu, Ion N.",
year = "2017",
abstract = "Modification of single and complex nickel-palladium samples by laser processing in the femtosecond time domain was studied. The samples were processed by focused Ti:Sapphire laser beam (Clark CPA-2101) with 775 nm laser wavelength, 2 kHz repetition rate, 200 fs pulse duration. The laser-induced morphological modifications have shown dependence on the applied fluences and number of laser pulses. The formed surface nanostructures on the single NiPd/Si and multilayer 5x(Ni/Pd)/Si systems are compared with individual Ni and Pd thin films. 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 number of pulses (less than 10 pulses) and low pulse energies range (not over 1.7 mu J), the two types of laser-induced periodic surface structure (LIPSS) can be observed: low and high spatial frequency LIPSS (HSFL and LSFL). For all samples, the measured LSFL periods were 720 nm for the ripples created solely on thin film surfaces during the single pulse action. In the case of the multi-pulse irradiation, the periodicities of created LSFLs on the all investigated thin films have shown tendency to reduction with increasing of pulse energies. (C) 2016 Elsevier B.V. All rights reserved.",
journal = "Applied Surface Science",
title = "Femtosecond laser processing of NiPd single and 5x(Ni/Pd) multilayer thin films",
volume = "417",
pages = "16-22",
doi = "10.1016/j.apsusc.2016.12.142"
}

Petrović, S., Gaković, B. M., Zamfirescu, M., Radu, C., Peruško, D., Radak, B., Ristoscu, C., Zdravković, S., Luculescu, C. L.,& Mihailescu, I. N.. (2017). Femtosecond laser processing of NiPd single and 5x(Ni/Pd) multilayer thin films. in Applied Surface Science, 417, 16-22.
https://doi.org/10.1016/j.apsusc.2016.12.142

Petrović S, Gaković BM, Zamfirescu M, Radu C, Peruško D, Radak B, Ristoscu C, Zdravković S, Luculescu CL, Mihailescu IN. Femtosecond laser processing of NiPd single and 5x(Ni/Pd) multilayer thin films. in Applied Surface Science. 2017;417:16-22.
doi:10.1016/j.apsusc.2016.12.142 .

Petrović, Suzana, Gaković, Biljana M., Zamfirescu, M., Radu, C., Peruško, Davor, Radak, Bojan, Ristoscu, Carmen, Zdravković, Slobodan, Luculescu, C. L., Mihailescu, Ion N., "Femtosecond laser processing of NiPd single and 5x(Ni/Pd) multilayer thin films" in Applied Surface Science, 417 (2017):16-22,
https://doi.org/10.1016/j.apsusc.2016.12.142 . .

TY  - JOUR
AU  - Gaković, Biljana M.
AU  - Petrović, Suzana
AU  - Albu, C.
AU  - Zamfirescu, M.
AU  - Panjan, Peter
AU  - Milovanović, Dubravka S.
AU  - Popescu-Pelin, G.
AU  - Mihailescu, Ion N.
PY  - 2017
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/1326
AB  - Processing of AlTiN/TiN multilayered hard coatings by femtosecond (fs) laser pulses has been investigated. Irradiation was performed in air with linearly polarized laser radiation with pulses of 200 fs duration at 775 nm wavelength. Single or 1000 subsequent laser pulses were directed at normal incidence towards target surface. Laser energy per pulse was adjusted from 0.5 to 50 mu J and corresponding fluence was 0.17-17.5 J cm(-2). The as deposited and laser-ablated samples were characterized by optical confocal microscopy, optical profilometry and scanning and transmition electron microscopy. In case of the AlTiN/TiN coating, a single-pulse damage threshold of 0.41 J cm(-2) was estimated. Well defined holes/craters with diameters from 7 to 35 mu m, up to 40 mu m depth were drilled, depending on laser pulse energy and number, after 1000 laser pulses. For small energy/fluence, laser induced periodical surface structures were observed. A model is discussed which can account for these features by the accumulation effect during multi-pulse irradiation. The forming craters can prove useful for fabrication of micron solid state lubricant reservoirs in the protective coating-steel system.
T2  - Optics and Laser Technology
T1  - Precise femtosecond laser crater fabrication in hard nanolayered AlTiN/TiN coating on steel substrate
VL  - 89
SP  - 200
EP  - 207
DO  - 10.1016/j.optlastec.2016.10.015
ER  - 

@article{
author = "Gaković, Biljana M. and Petrović, Suzana and Albu, C. and Zamfirescu, M. and Panjan, Peter and Milovanović, Dubravka S. and Popescu-Pelin, G. and Mihailescu, Ion N.",
year = "2017",
abstract = "Processing of AlTiN/TiN multilayered hard coatings by femtosecond (fs) laser pulses has been investigated. Irradiation was performed in air with linearly polarized laser radiation with pulses of 200 fs duration at 775 nm wavelength. Single or 1000 subsequent laser pulses were directed at normal incidence towards target surface. Laser energy per pulse was adjusted from 0.5 to 50 mu J and corresponding fluence was 0.17-17.5 J cm(-2). The as deposited and laser-ablated samples were characterized by optical confocal microscopy, optical profilometry and scanning and transmition electron microscopy. In case of the AlTiN/TiN coating, a single-pulse damage threshold of 0.41 J cm(-2) was estimated. Well defined holes/craters with diameters from 7 to 35 mu m, up to 40 mu m depth were drilled, depending on laser pulse energy and number, after 1000 laser pulses. For small energy/fluence, laser induced periodical surface structures were observed. A model is discussed which can account for these features by the accumulation effect during multi-pulse irradiation. The forming craters can prove useful for fabrication of micron solid state lubricant reservoirs in the protective coating-steel system.",
journal = "Optics and Laser Technology",
title = "Precise femtosecond laser crater fabrication in hard nanolayered AlTiN/TiN coating on steel substrate",
volume = "89",
pages = "200-207",
doi = "10.1016/j.optlastec.2016.10.015"
}

Gaković, B. M., Petrović, S., Albu, C., Zamfirescu, M., Panjan, P., Milovanović, D. S., Popescu-Pelin, G.,& Mihailescu, I. N.. (2017). Precise femtosecond laser crater fabrication in hard nanolayered AlTiN/TiN coating on steel substrate. in Optics and Laser Technology, 89, 200-207.
https://doi.org/10.1016/j.optlastec.2016.10.015

Gaković BM, Petrović S, Albu C, Zamfirescu M, Panjan P, Milovanović DS, Popescu-Pelin G, Mihailescu IN. Precise femtosecond laser crater fabrication in hard nanolayered AlTiN/TiN coating on steel substrate. in Optics and Laser Technology. 2017;89:200-207.
doi:10.1016/j.optlastec.2016.10.015 .

Gaković, Biljana M., Petrović, Suzana, Albu, C., Zamfirescu, M., Panjan, Peter, Milovanović, Dubravka S., Popescu-Pelin, G., Mihailescu, Ion N., "Precise femtosecond laser crater fabrication in hard nanolayered AlTiN/TiN coating on steel substrate" in Optics and Laser Technology, 89 (2017):200-207,
https://doi.org/10.1016/j.optlastec.2016.10.015 . .

TY  - JOUR
AU  - Bjelajac, Anđelika
AU  - Đokić, Veljko R.
AU  - Petrović, Rada
AU  - Bundaleski, Nenad
AU  - Socol, Gabriel
AU  - Mihailescu, Ion N.
AU  - Rakočević, Zlatko Lj.
AU  - Janaćković, Đorđe T.
PY  - 2017
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/1786
AB  - A process of obtaining N-doped TiO2 nanotubes sensitized by CdS nanoparticles is presented, including detailed characterizations performed along the synthesis. Transparent TiO2 films consisting of nanotubes, 2.5 mu m long and of similar to 60 nm inner diameter, were obtained after anodization of a titanium film deposited onto FTO glass substrate. N-doping was achieved by annealing of TiO2 film in ammonia. X-ray Photoelectron Spectroscopy measurements showed that nitrogen was substitutionally incorporated in the TiO2 matrix, with the N:Ti concentration ratio of 1:100. The doping changed the optical properties of the material in such a way that the absorption edge was shifted from 380 nm to 507 nm, as observed from diffuse reflectance spectra. The influence of the microwave (MW) irradiation on the synthesized CdS quantum dots and their optical properties was investigated. It was shown that the diameter of CdS nanoparticles was increased due to releasing of S-2-ions from dimethyl sulfoxide (DMSO) as a consequence of the MW treatment. The (N)TiO2 films were then used as substrates for matrix assisted pulsed laser deposition of the CdS quantum dots with DMSO as a matrix. The laser parameters for the deposition were optimized in order to preserve the nanotubular structure open, the latter being an important feature of this type of photoanode. The structure obtained under optimized conditions has an additional absorption edge shift, reaching 603 nm.
T2  - Ceramics International
T1  - Absorption boost of TiO2 nanotubes by doping with N and sensitization with CdS quantum dots
VL  - 43
IS  - 17
SP  - 15040
EP  - 15046
DO  - 10.1016/j.ceramint.2017.08.029
ER  - 

@article{
author = "Bjelajac, Anđelika and Đokić, Veljko R. and Petrović, Rada and Bundaleski, Nenad and Socol, Gabriel and Mihailescu, Ion N. and Rakočević, Zlatko Lj. and Janaćković, Đorđe T.",
year = "2017",
abstract = "A process of obtaining N-doped TiO2 nanotubes sensitized by CdS nanoparticles is presented, including detailed characterizations performed along the synthesis. Transparent TiO2 films consisting of nanotubes, 2.5 mu m long and of similar to 60 nm inner diameter, were obtained after anodization of a titanium film deposited onto FTO glass substrate. N-doping was achieved by annealing of TiO2 film in ammonia. X-ray Photoelectron Spectroscopy measurements showed that nitrogen was substitutionally incorporated in the TiO2 matrix, with the N:Ti concentration ratio of 1:100. The doping changed the optical properties of the material in such a way that the absorption edge was shifted from 380 nm to 507 nm, as observed from diffuse reflectance spectra. The influence of the microwave (MW) irradiation on the synthesized CdS quantum dots and their optical properties was investigated. It was shown that the diameter of CdS nanoparticles was increased due to releasing of S-2-ions from dimethyl sulfoxide (DMSO) as a consequence of the MW treatment. The (N)TiO2 films were then used as substrates for matrix assisted pulsed laser deposition of the CdS quantum dots with DMSO as a matrix. The laser parameters for the deposition were optimized in order to preserve the nanotubular structure open, the latter being an important feature of this type of photoanode. The structure obtained under optimized conditions has an additional absorption edge shift, reaching 603 nm.",
journal = "Ceramics International",
title = "Absorption boost of TiO2 nanotubes by doping with N and sensitization with CdS quantum dots",
volume = "43",
number = "17",
pages = "15040-15046",
doi = "10.1016/j.ceramint.2017.08.029"
}

Bjelajac, A., Đokić, V. R., Petrović, R., Bundaleski, N., Socol, G., Mihailescu, I. N., Rakočević, Z. Lj.,& Janaćković, Đ. T.. (2017). Absorption boost of TiO2 nanotubes by doping with N and sensitization with CdS quantum dots. in Ceramics International, 43(17), 15040-15046.
https://doi.org/10.1016/j.ceramint.2017.08.029

Bjelajac A, Đokić VR, Petrović R, Bundaleski N, Socol G, Mihailescu IN, Rakočević ZL, Janaćković ĐT. Absorption boost of TiO2 nanotubes by doping with N and sensitization with CdS quantum dots. in Ceramics International. 2017;43(17):15040-15046.
doi:10.1016/j.ceramint.2017.08.029 .

Bjelajac, Anđelika, Đokić, Veljko R., Petrović, Rada, Bundaleski, Nenad, Socol, Gabriel, Mihailescu, Ion N., Rakočević, Zlatko Lj., Janaćković, Đorđe T., "Absorption boost of TiO2 nanotubes by doping with N and sensitization with CdS quantum dots" in Ceramics International, 43, no. 17 (2017):15040-15046,
https://doi.org/10.1016/j.ceramint.2017.08.029 . .

TY  - JOUR
AU  - Milovanović, Dubravka S.
AU  - Gaković, Biljana M.
AU  - Radu, C.
AU  - Zamfirescu, M.
AU  - Radak, Bojan
AU  - Petrović, Suzana
AU  - Rogić Miladinović, Zorana
AU  - Mihailescu, Ion N.
PY  - 2014
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/7058
AB  - In this work, we present the results obtained by femtosecond laser processing of AISI D2 steel and the widely applicable titanium-based alloy, Ti6Al4V. Patterning the materials surfaces was done by a Ti: sapphire system at 775 nm wavelength and 200 fs pulse duration, while varying the output pulse energies and the scanning speed. The formation of laser-induced periodical surface structures were found for both materials.
T2  - Physica Scripta
T1  - Femtosecond laser surface patterning of steel and titanium alloy
VL  - T162
DO  - 10.1088/0031-8949/2014/T162/014017
ER  - 

@article{
author = "Milovanović, Dubravka S. and Gaković, Biljana M. and Radu, C. and Zamfirescu, M. and Radak, Bojan and Petrović, Suzana and Rogić Miladinović, Zorana and Mihailescu, Ion N.",
year = "2014",
abstract = "In this work, we present the results obtained by femtosecond laser processing of AISI D2 steel and the widely applicable titanium-based alloy, Ti6Al4V. Patterning the materials surfaces was done by a Ti: sapphire system at 775 nm wavelength and 200 fs pulse duration, while varying the output pulse energies and the scanning speed. The formation of laser-induced periodical surface structures were found for both materials.",
journal = "Physica Scripta",
title = "Femtosecond laser surface patterning of steel and titanium alloy",
volume = "T162",
doi = "10.1088/0031-8949/2014/T162/014017"
}

Milovanović, D. S., Gaković, B. M., Radu, C., Zamfirescu, M., Radak, B., Petrović, S., Rogić Miladinović, Z.,& Mihailescu, I. N.. (2014). Femtosecond laser surface patterning of steel and titanium alloy. in Physica Scripta, T162.
https://doi.org/10.1088/0031-8949/2014/T162/014017

Milovanović DS, Gaković BM, Radu C, Zamfirescu M, Radak B, Petrović S, Rogić Miladinović Z, Mihailescu IN. Femtosecond laser surface patterning of steel and titanium alloy. in Physica Scripta. 2014;T162.
doi:10.1088/0031-8949/2014/T162/014017 .

Milovanović, Dubravka S., Gaković, Biljana M., Radu, C., Zamfirescu, M., Radak, Bojan, Petrović, Suzana, Rogić Miladinović, Zorana, Mihailescu, Ion N., "Femtosecond laser surface patterning of steel and titanium alloy" in Physica Scripta, T162 (2014),
https://doi.org/10.1088/0031-8949/2014/T162/014017 . .

TY  - JOUR
AU  - Stašić, Jelena
AU  - Joksić, Gordana
AU  - Živković, Ljiljana
AU  - Mihailescu, Ion N.
AU  - Ghica, Corneliu
AU  - Kuncser, Andrei
AU  - Trtica, Milan
PY  - 2014
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/207
AB  - Silver nanoparticles were obtained by picosecond laser ablation in water at 1064 nm, using focusing geometry to design the particles size. The position of the target surface with respect to the focal point strongly influences the NPs size: above and in the focus it is up to 20 nm and below focus LT = 150 nm. Generated particles have a spherical shape. The solutions were further employed on human cells and the tests showed a deteriorating effect on DNA.
T2  - Laser Physics
T1  - Focusing geometry-induced size tailoring of silver nanoparticles obtained by laser ablation in water
VL  - 24
IS  - 10
DO  - 10.1088/1054-660X/24/10/106005
ER  - 

@article{
author = "Stašić, Jelena and Joksić, Gordana and Živković, Ljiljana and Mihailescu, Ion N. and Ghica, Corneliu and Kuncser, Andrei and Trtica, Milan",
year = "2014",
abstract = "Silver nanoparticles were obtained by picosecond laser ablation in water at 1064 nm, using focusing geometry to design the particles size. The position of the target surface with respect to the focal point strongly influences the NPs size: above and in the focus it is up to 20 nm and below focus LT = 150 nm. Generated particles have a spherical shape. The solutions were further employed on human cells and the tests showed a deteriorating effect on DNA.",
journal = "Laser Physics",
title = "Focusing geometry-induced size tailoring of silver nanoparticles obtained by laser ablation in water",
volume = "24",
number = "10",
doi = "10.1088/1054-660X/24/10/106005"
}

Stašić, J., Joksić, G., Živković, L., Mihailescu, I. N., Ghica, C., Kuncser, A.,& Trtica, M.. (2014). Focusing geometry-induced size tailoring of silver nanoparticles obtained by laser ablation in water. in Laser Physics, 24(10).
https://doi.org/10.1088/1054-660X/24/10/106005

Stašić J, Joksić G, Živković L, Mihailescu IN, Ghica C, Kuncser A, Trtica M. Focusing geometry-induced size tailoring of silver nanoparticles obtained by laser ablation in water. in Laser Physics. 2014;24(10).
doi:10.1088/1054-660X/24/10/106005 .

Stašić, Jelena, Joksić, Gordana, Živković, Ljiljana, Mihailescu, Ion N., Ghica, Corneliu, Kuncser, Andrei, Trtica, Milan, "Focusing geometry-induced size tailoring of silver nanoparticles obtained by laser ablation in water" in Laser Physics, 24, no. 10 (2014),
https://doi.org/10.1088/1054-660X/24/10/106005 . .

TY  - JOUR
AU  - Gaković, Biljana M.
AU  - Radak, Bojan
AU  - Radu, C.
AU  - Zamfirescu, M.
AU  - Trtica, Milan
AU  - Petrović, Suzana
AU  - Stašić, Jelena
AU  - Panjan, Peter
AU  - Mihailescu, Ion N.
PY  - 2012
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/4993
AB  - We studied surface modification of a double layer protective coating on steel induced by single fs laser pulse irradiation in ambient air. The outer alumina (Al2O3) layer, which protects against aggressive environments, was 1.7 mu m thick and the titanium aluminum nitride (TiAlN) layer in contact with the steel surface had a thickness of 1.9 mu m. The pulses (lambda=775 nm, tau=200 fs) were generated by a Ti:sapphire laser source. The pulse energy was varied from 0.32 mu J to 50 mu J, corresponding to an incident laser fluence of 0.11 J cm(-2) to 16.47 J cm(-2). The surface damage threshold was found to be 0.20 J cm(-2) and the alumina layer removal was initiated at 0.56 J cm(-2). This selective ablation of alumina was possible in a wide range of fluences, up to the maximum applied, without ablating the TiAlN layer beneath. (C) 2012 Elsevier B.V. All rights reserved.
T2  - Surface and Coatings Technology
T1  - Selective single pulse femtosecond laser removal of alumina (Al2O3) from a bilayered Al2O3/TiAlN/steel coating
VL  - 206
IS  - 24
SP  - 5080
EP  - 5084
DO  - 10.1016/j.surfcoat.2012.06.021
ER  - 

@article{
author = "Gaković, Biljana M. and Radak, Bojan and Radu, C. and Zamfirescu, M. and Trtica, Milan and Petrović, Suzana and Stašić, Jelena and Panjan, Peter and Mihailescu, Ion N.",
year = "2012",
abstract = "We studied surface modification of a double layer protective coating on steel induced by single fs laser pulse irradiation in ambient air. The outer alumina (Al2O3) layer, which protects against aggressive environments, was 1.7 mu m thick and the titanium aluminum nitride (TiAlN) layer in contact with the steel surface had a thickness of 1.9 mu m. The pulses (lambda=775 nm, tau=200 fs) were generated by a Ti:sapphire laser source. The pulse energy was varied from 0.32 mu J to 50 mu J, corresponding to an incident laser fluence of 0.11 J cm(-2) to 16.47 J cm(-2). The surface damage threshold was found to be 0.20 J cm(-2) and the alumina layer removal was initiated at 0.56 J cm(-2). This selective ablation of alumina was possible in a wide range of fluences, up to the maximum applied, without ablating the TiAlN layer beneath. (C) 2012 Elsevier B.V. All rights reserved.",
journal = "Surface and Coatings Technology",
title = "Selective single pulse femtosecond laser removal of alumina (Al2O3) from a bilayered Al2O3/TiAlN/steel coating",
volume = "206",
number = "24",
pages = "5080-5084",
doi = "10.1016/j.surfcoat.2012.06.021"
}

Gaković, B. M., Radak, B., Radu, C., Zamfirescu, M., Trtica, M., Petrović, S., Stašić, J., Panjan, P.,& Mihailescu, I. N.. (2012). Selective single pulse femtosecond laser removal of alumina (Al2O3) from a bilayered Al2O3/TiAlN/steel coating. in Surface and Coatings Technology, 206(24), 5080-5084.
https://doi.org/10.1016/j.surfcoat.2012.06.021

Gaković BM, Radak B, Radu C, Zamfirescu M, Trtica M, Petrović S, Stašić J, Panjan P, Mihailescu IN. Selective single pulse femtosecond laser removal of alumina (Al2O3) from a bilayered Al2O3/TiAlN/steel coating. in Surface and Coatings Technology. 2012;206(24):5080-5084.
doi:10.1016/j.surfcoat.2012.06.021 .

Gaković, Biljana M., Radak, Bojan, Radu, C., Zamfirescu, M., Trtica, Milan, Petrović, Suzana, Stašić, Jelena, Panjan, Peter, Mihailescu, Ion N., "Selective single pulse femtosecond laser removal of alumina (Al2O3) from a bilayered Al2O3/TiAlN/steel coating" in Surface and Coatings Technology, 206, no. 24 (2012):5080-5084,
https://doi.org/10.1016/j.surfcoat.2012.06.021 . .

TY  - JOUR
AU  - Gaković, Biljana M.
AU  - Radu, C.
AU  - Zamfirescu, M.
AU  - Radak, Bojan
AU  - Trtica, Milan
AU  - Petrović, Suzana
AU  - Panjan, Peter
AU  - Zupanic, F.
AU  - Ristoscu, Carmen
AU  - Mihailescu, Ion N.
PY  - 2011
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/4501
AB  - A target of multilayered TiAlN/TiN coating deposited on steel was irradiated by 200 fs pulses of a Ti:Sapphire laser, operating at 775 nm. Laser fluences of 1.16 J cm(-2) to 116 J cm(-2) produced a range of modifications, from well defined parallel surface structures on the coating, to deep craters in the substrate. Parameters for coating ablation were determined in terms of laser fluence and pulse count. A single-pulse damage threshold was found to be 0.66 J cm(-2) and the damage incubation factor 0.642. At lower laser fluences formation of laser induced parallel surface structures was evident, beginning from the first pulse, with a periodicity of about 580 nm. These structures remained and were pronounced at the rim of the damage spot even when the coating was completely ablated in the centre. (C) 2011 Elsevier B.V. All rights reserved.
T2  - Surface and Coatings Technology
T1  - Femtosecond laser modification of multilayered TiAlN/TiN coating
VL  - 206
IS  - 2-3
SP  - 411
EP  - 416
DO  - 10.1016/j.surfcoat.2011.07.042
ER  - 

@article{
author = "Gaković, Biljana M. and Radu, C. and Zamfirescu, M. and Radak, Bojan and Trtica, Milan and Petrović, Suzana and Panjan, Peter and Zupanic, F. and Ristoscu, Carmen and Mihailescu, Ion N.",
year = "2011",
abstract = "A target of multilayered TiAlN/TiN coating deposited on steel was irradiated by 200 fs pulses of a Ti:Sapphire laser, operating at 775 nm. Laser fluences of 1.16 J cm(-2) to 116 J cm(-2) produced a range of modifications, from well defined parallel surface structures on the coating, to deep craters in the substrate. Parameters for coating ablation were determined in terms of laser fluence and pulse count. A single-pulse damage threshold was found to be 0.66 J cm(-2) and the damage incubation factor 0.642. At lower laser fluences formation of laser induced parallel surface structures was evident, beginning from the first pulse, with a periodicity of about 580 nm. These structures remained and were pronounced at the rim of the damage spot even when the coating was completely ablated in the centre. (C) 2011 Elsevier B.V. All rights reserved.",
journal = "Surface and Coatings Technology",
title = "Femtosecond laser modification of multilayered TiAlN/TiN coating",
volume = "206",
number = "2-3",
pages = "411-416",
doi = "10.1016/j.surfcoat.2011.07.042"
}

Gaković, B. M., Radu, C., Zamfirescu, M., Radak, B., Trtica, M., Petrović, S., Panjan, P., Zupanic, F., Ristoscu, C.,& Mihailescu, I. N.. (2011). Femtosecond laser modification of multilayered TiAlN/TiN coating. in Surface and Coatings Technology, 206(2-3), 411-416.
https://doi.org/10.1016/j.surfcoat.2011.07.042

Gaković BM, Radu C, Zamfirescu M, Radak B, Trtica M, Petrović S, Panjan P, Zupanic F, Ristoscu C, Mihailescu IN. Femtosecond laser modification of multilayered TiAlN/TiN coating. in Surface and Coatings Technology. 2011;206(2-3):411-416.
doi:10.1016/j.surfcoat.2011.07.042 .

Gaković, Biljana M., Radu, C., Zamfirescu, M., Radak, Bojan, Trtica, Milan, Petrović, Suzana, Panjan, Peter, Zupanic, F., Ristoscu, Carmen, Mihailescu, Ion N., "Femtosecond laser modification of multilayered TiAlN/TiN coating" in Surface and Coatings Technology, 206, no. 2-3 (2011):411-416,
https://doi.org/10.1016/j.surfcoat.2011.07.042 . .

TY  - CONF
AU  - Tanaskovic, D.
AU  - Veljović, Đorđe N.
AU  - Petrovic, R.
AU  - Janaćković, Đorđe T.
AU  - Mitrić, Miodrag
AU  - Cojanu, C.
AU  - Ristoscu, Carmen
AU  - Mihailescu, Ion N.
PY  - 2008
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/6718
AB  - Pulsed laser deposition was used to obtain functionally graded bioactive glass coatings on titanium substrates. An UV KrF* (lambda=248 nm, tau GT 7 ns) excimer laser was used for the multi-pulse irradiation of the targets. The depositions were performed in oxygen while keeping substrate temperature at 400 degrees C. We used sintered glass targets in the system SiO2-Na2O-K2O-CaO-MgO-P2O5 that differed in SiO2 content, which was either 57 wt.% (6P57) or 61 wt.% (6P61). A glass 6P61 was used as the first layer in direct contact with the metallic substrate, while the outer bioactive layer was made of glass 6P57. Both the bioactive coatings and the bulk glasses were analyzed by Fourier transform infrared spectrometry (FTIR), grazing incidence X-ray diffraction (GIXRD), and scanning electron microscopy (SEM). The FTIR spectra of the glass powders and glass coatings showed the main vibration modes of the Si-O-Si groups. GIXRD analysis confirmed that the glass coatings had an amorphous structure. The SEM micrographs of the glass coatings showed the films to consist of droplets with diameters ranging from 0.2 to 5 Pm. SEM was used to determine the rate of apatite formation on the coating when exposed to simulated body fluid (SBF) solution for 7 days. We demonstrated that pulsed laser deposition leads to good glass-metal adhesion on the substrate and well attached bioactive particles on the surface. We consider therefore this method appropriate for forming implants that can develop an apatite layer after immersion in SBF.
C3  - Key Engineering Materials
T1  - Double-layer bioactive glass coatings obtained by pulsed laser deposition
VL  - 361-363
SP  - 277
EP  - +
UR  - https://hdl.handle.net/21.15107/rcub_vinar_6718
ER  - 

@conference{
author = "Tanaskovic, D. and Veljović, Đorđe N. and Petrovic, R. and Janaćković, Đorđe T. and Mitrić, Miodrag and Cojanu, C. and Ristoscu, Carmen and Mihailescu, Ion N.",
year = "2008",
abstract = "Pulsed laser deposition was used to obtain functionally graded bioactive glass coatings on titanium substrates. An UV KrF* (lambda=248 nm, tau GT 7 ns) excimer laser was used for the multi-pulse irradiation of the targets. The depositions were performed in oxygen while keeping substrate temperature at 400 degrees C. We used sintered glass targets in the system SiO2-Na2O-K2O-CaO-MgO-P2O5 that differed in SiO2 content, which was either 57 wt.% (6P57) or 61 wt.% (6P61). A glass 6P61 was used as the first layer in direct contact with the metallic substrate, while the outer bioactive layer was made of glass 6P57. Both the bioactive coatings and the bulk glasses were analyzed by Fourier transform infrared spectrometry (FTIR), grazing incidence X-ray diffraction (GIXRD), and scanning electron microscopy (SEM). The FTIR spectra of the glass powders and glass coatings showed the main vibration modes of the Si-O-Si groups. GIXRD analysis confirmed that the glass coatings had an amorphous structure. The SEM micrographs of the glass coatings showed the films to consist of droplets with diameters ranging from 0.2 to 5 Pm. SEM was used to determine the rate of apatite formation on the coating when exposed to simulated body fluid (SBF) solution for 7 days. We demonstrated that pulsed laser deposition leads to good glass-metal adhesion on the substrate and well attached bioactive particles on the surface. We consider therefore this method appropriate for forming implants that can develop an apatite layer after immersion in SBF.",
journal = "Key Engineering Materials",
title = "Double-layer bioactive glass coatings obtained by pulsed laser deposition",
volume = "361-363",
pages = "277-+",
url = "https://hdl.handle.net/21.15107/rcub_vinar_6718"
}

Tanaskovic, D., Veljović, Đ. N., Petrovic, R., Janaćković, Đ. T., Mitrić, M., Cojanu, C., Ristoscu, C.,& Mihailescu, I. N.. (2008). Double-layer bioactive glass coatings obtained by pulsed laser deposition. in Key Engineering Materials, 361-363, 277-+.
https://hdl.handle.net/21.15107/rcub_vinar_6718

Tanaskovic D, Veljović ĐN, Petrovic R, Janaćković ĐT, Mitrić M, Cojanu C, Ristoscu C, Mihailescu IN. Double-layer bioactive glass coatings obtained by pulsed laser deposition. in Key Engineering Materials. 2008;361-363:277-+.
https://hdl.handle.net/21.15107/rcub_vinar_6718 .

Tanaskovic, D., Veljović, Đorđe N., Petrovic, R., Janaćković, Đorđe T., Mitrić, Miodrag, Cojanu, C., Ristoscu, Carmen, Mihailescu, Ion N., "Double-layer bioactive glass coatings obtained by pulsed laser deposition" in Key Engineering Materials, 361-363 (2008):277-+,
https://hdl.handle.net/21.15107/rcub_vinar_6718 .