TY  - CONF
AU  - Jovanović, Sonja
AU  - Rmuš Mravik, Jelena
AU  - Grujičić, Marija
AU  - Petković, Darija
AU  - Pejčić, Milica
AU  - Jovanović, Zoran
PY  - 2023
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/11659
AB  - In the past two decades spinel ferrites nanoparticles have been extensively investigated due to their potential applications in a variety of fields (data storage, catalysis, energy, environment, biomedicine, etc.). In the present work, zinc ferrite nanoparticles with different copper content (Zn(1-x)CuxFe2O4; x=0, 0.2, 0.4, 0.6, and 0.8) but with the same particle size distribution and amount of oleic acid as capping agent were prepared by solvothermal synthesis and the physicochemical properties of as-prepared samples were investigated. The prepared samples were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR) and vibrating sample magnetometry (VSM). The XRD results show that all the diffraction maxima correspond to the cubic spinel structure, while TEM images reviled that samples are consisted of sphere-like particles, 5-7 nm in size. The presence of oleic acid on the surface of nanoparticles was confirmed by FTIR analysis. The magnetic measurements revealed superparamagnetic behavior of obtained powders, with gradual increase of saturation magnetization.
PB  - Belgrade : Materials Research Society of Serbia
C3  - YUCOMAT 2023 : 24th Annual Conference YUCOMAT 2023 : programme and the book of abstracts; September 4-8, 2023; Herceg Novi, Montenegro
T1  - Physicochemical properties of solvothermaly synthesized zinc copper ferrite nanoparticles
SP  - 157
UR  - https://hdl.handle.net/21.15107/rcub_vinar_11659
ER  - 

@conference{
author = "Jovanović, Sonja and Rmuš Mravik, Jelena and Grujičić, Marija and Petković, Darija and Pejčić, Milica and Jovanović, Zoran",
year = "2023",
abstract = "In the past two decades spinel ferrites nanoparticles have been extensively investigated due to their potential applications in a variety of fields (data storage, catalysis, energy, environment, biomedicine, etc.). In the present work, zinc ferrite nanoparticles with different copper content (Zn(1-x)CuxFe2O4; x=0, 0.2, 0.4, 0.6, and 0.8) but with the same particle size distribution and amount of oleic acid as capping agent were prepared by solvothermal synthesis and the physicochemical properties of as-prepared samples were investigated. The prepared samples were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR) and vibrating sample magnetometry (VSM). The XRD results show that all the diffraction maxima correspond to the cubic spinel structure, while TEM images reviled that samples are consisted of sphere-like particles, 5-7 nm in size. The presence of oleic acid on the surface of nanoparticles was confirmed by FTIR analysis. The magnetic measurements revealed superparamagnetic behavior of obtained powders, with gradual increase of saturation magnetization.",
publisher = "Belgrade : Materials Research Society of Serbia",
journal = "YUCOMAT 2023 : 24th Annual Conference YUCOMAT 2023 : programme and the book of abstracts; September 4-8, 2023; Herceg Novi, Montenegro",
title = "Physicochemical properties of solvothermaly synthesized zinc copper ferrite nanoparticles",
pages = "157",
url = "https://hdl.handle.net/21.15107/rcub_vinar_11659"
}

Jovanović, S., Rmuš Mravik, J., Grujičić, M., Petković, D., Pejčić, M.,& Jovanović, Z.. (2023). Physicochemical properties of solvothermaly synthesized zinc copper ferrite nanoparticles. in YUCOMAT 2023 : 24th Annual Conference YUCOMAT 2023 : programme and the book of abstracts; September 4-8, 2023; Herceg Novi, Montenegro
Belgrade : Materials Research Society of Serbia., 157.
https://hdl.handle.net/21.15107/rcub_vinar_11659

Jovanović S, Rmuš Mravik J, Grujičić M, Petković D, Pejčić M, Jovanović Z. Physicochemical properties of solvothermaly synthesized zinc copper ferrite nanoparticles. in YUCOMAT 2023 : 24th Annual Conference YUCOMAT 2023 : programme and the book of abstracts; September 4-8, 2023; Herceg Novi, Montenegro. 2023;:157.
https://hdl.handle.net/21.15107/rcub_vinar_11659 .

Jovanović, Sonja, Rmuš Mravik, Jelena, Grujičić, Marija, Petković, Darija, Pejčić, Milica, Jovanović, Zoran, "Physicochemical properties of solvothermaly synthesized zinc copper ferrite nanoparticles" in YUCOMAT 2023 : 24th Annual Conference YUCOMAT 2023 : programme and the book of abstracts; September 4-8, 2023; Herceg Novi, Montenegro (2023):157,
https://hdl.handle.net/21.15107/rcub_vinar_11659 .

TY  - CONF
AU  - Mravik, Željko
AU  - Pejčić, Milica
AU  - Grujičić, Marija
AU  - Rmuš Mravik, Jelena
AU  - Stević, Miša
AU  - Stević, Zoran
AU  - Jovanović, Zoran
PY  - 2023
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/12314
AB  - In sensor devices the material of choice should be highly dependent on perturbation of environmental parameters. In order to achieve good sensitivity and selectivity of sensing devices to temperature, humidity or concentration of different gasses, the materials with adjustable properties are highly desirable. Electric properties of graphene oxide (GO) can be easily tuned by modification of surface chemistry and anchoring of functional compounds onto its two-dimensional structure. Prior to application of sensing device, research and development of materials system is the most essential step. In this work, the formation of GO and GO/12-tungstophosphoric acid (WPA) films with 6 wt.% of WPA on interdigital electrodes was investigated by variation of dip-coating parameters (receding angle and time between steps). Obtained films were thermally reduced in argon atmosphere after which optical microscopy was used to evaluate morphology and stability of deposited GO and GO/WPA films. Impedance spectroscopy was used to investigate the electric properties of the obtained films in range from 10 Hz to 100 kHz. Measured impedance values were correlated to the degree of material detachment and deposition parameters i.e. films showing the lowest impedance values had the smallest area of detached film. Additionally, impedance values were measured depending on the environment temperature which showed that GO/WPA films exhibit the lowest impedance values and good sensitivity to changes of temperature making it good a candidate for sensing devices.
PB  - Belgrade : Institute of Technical Sciences of SASA
C3  - 21st Young Researchers' Conference Materials Sciences and Engineering : program and the book of abstracts
T1  - Temperature dependence of electric properties of GO and GO/WPA films on interdigital electrodes
SP  - 40
EP  - 40
UR  - https://hdl.handle.net/21.15107/rcub_vinar_12314
ER  - 

@conference{
author = "Mravik, Željko and Pejčić, Milica and Grujičić, Marija and Rmuš Mravik, Jelena and Stević, Miša and Stević, Zoran and Jovanović, Zoran",
year = "2023",
abstract = "In sensor devices the material of choice should be highly dependent on perturbation of environmental parameters. In order to achieve good sensitivity and selectivity of sensing devices to temperature, humidity or concentration of different gasses, the materials with adjustable properties are highly desirable. Electric properties of graphene oxide (GO) can be easily tuned by modification of surface chemistry and anchoring of functional compounds onto its two-dimensional structure. Prior to application of sensing device, research and development of materials system is the most essential step. In this work, the formation of GO and GO/12-tungstophosphoric acid (WPA) films with 6 wt.% of WPA on interdigital electrodes was investigated by variation of dip-coating parameters (receding angle and time between steps). Obtained films were thermally reduced in argon atmosphere after which optical microscopy was used to evaluate morphology and stability of deposited GO and GO/WPA films. Impedance spectroscopy was used to investigate the electric properties of the obtained films in range from 10 Hz to 100 kHz. Measured impedance values were correlated to the degree of material detachment and deposition parameters i.e. films showing the lowest impedance values had the smallest area of detached film. Additionally, impedance values were measured depending on the environment temperature which showed that GO/WPA films exhibit the lowest impedance values and good sensitivity to changes of temperature making it good a candidate for sensing devices.",
publisher = "Belgrade : Institute of Technical Sciences of SASA",
journal = "21st Young Researchers' Conference Materials Sciences and Engineering : program and the book of abstracts",
title = "Temperature dependence of electric properties of GO and GO/WPA films on interdigital electrodes",
pages = "40-40",
url = "https://hdl.handle.net/21.15107/rcub_vinar_12314"
}

Mravik, Ž., Pejčić, M., Grujičić, M., Rmuš Mravik, J., Stević, M., Stević, Z.,& Jovanović, Z.. (2023). Temperature dependence of electric properties of GO and GO/WPA films on interdigital electrodes. in 21st Young Researchers' Conference Materials Sciences and Engineering : program and the book of abstracts
Belgrade : Institute of Technical Sciences of SASA., 40-40.
https://hdl.handle.net/21.15107/rcub_vinar_12314

Mravik Ž, Pejčić M, Grujičić M, Rmuš Mravik J, Stević M, Stević Z, Jovanović Z. Temperature dependence of electric properties of GO and GO/WPA films on interdigital electrodes. in 21st Young Researchers' Conference Materials Sciences and Engineering : program and the book of abstracts. 2023;:40-40.
https://hdl.handle.net/21.15107/rcub_vinar_12314 .

Mravik, Željko, Pejčić, Milica, Grujičić, Marija, Rmuš Mravik, Jelena, Stević, Miša, Stević, Zoran, Jovanović, Zoran, "Temperature dependence of electric properties of GO and GO/WPA films on interdigital electrodes" in 21st Young Researchers' Conference Materials Sciences and Engineering : program and the book of abstracts (2023):40-40,
https://hdl.handle.net/21.15107/rcub_vinar_12314 .

TY  - CONF
AU  - Pejčić, Milica
AU  - Mravik, Željko
AU  - Bajuk-Bogdanović, Danica
AU  - Grujičić, Marija
AU  - Rmuš Mravik, Jelena
AU  - Jovanović, Sonja
AU  - Jovanović, Zoran
PY  - 2023
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/12316
AB  - Different hierarchical ordering of nanomaterials, either as individual components or in the form of nanocomposites, is one of the approaches used for the development of supercapacitors. In this work, the effect of hydrothermal treatment on oxygen functional groups of nanocomposites between graphene oxide (GO), 12-tungstophosphoric acid (WPA), and 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA) was examined. The mentioned materials were hydrothermally treated for 4, 8 and 12 hours at 180 °C in order to understand how interaction between the components is influencing development of surface chemistry. The results of Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy (Raman), and temperature-programmed desorption (TPD) are showing the surface and structural changes of GO (individually and in nanocomposite) as a result of hydrothermal treatment. Both FTIR and RAMAN confirm the presence of WPA and PTCDA. Additionally, it appears that hydrothermal treatment has no impact on the structural changes in PTCDA, which is consistent across various temperature conditions. TPD results indicate that prolonged hydrothermal treatment leads to a gradual increase of the number of functional groups of GO. However, the number of desorbed groups is influenced by the WPA and PTDCA components. This research offers new insights into GO, WPA, and PTCDA interactions which can have useful implications for development of electrochemical supercapacitors.
PB  - Belgrade : Institute of Technical Sciences of SASA
C3  - 21st Young Researchers' Conference Materials Sciences and Engineering : program and the book of abstracts
T1  - Investigating the influence of hydrothermal treatment on oxygen functional groups in graphene oxide-based nanocomposites
SP  - 43
EP  - 43
UR  - https://hdl.handle.net/21.15107/rcub_vinar_12316
ER  - 

@conference{
author = "Pejčić, Milica and Mravik, Željko and Bajuk-Bogdanović, Danica and Grujičić, Marija and Rmuš Mravik, Jelena and Jovanović, Sonja and Jovanović, Zoran",
year = "2023",
abstract = "Different hierarchical ordering of nanomaterials, either as individual components or in the form of nanocomposites, is one of the approaches used for the development of supercapacitors. In this work, the effect of hydrothermal treatment on oxygen functional groups of nanocomposites between graphene oxide (GO), 12-tungstophosphoric acid (WPA), and 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA) was examined. The mentioned materials were hydrothermally treated for 4, 8 and 12 hours at 180 °C in order to understand how interaction between the components is influencing development of surface chemistry. The results of Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy (Raman), and temperature-programmed desorption (TPD) are showing the surface and structural changes of GO (individually and in nanocomposite) as a result of hydrothermal treatment. Both FTIR and RAMAN confirm the presence of WPA and PTCDA. Additionally, it appears that hydrothermal treatment has no impact on the structural changes in PTCDA, which is consistent across various temperature conditions. TPD results indicate that prolonged hydrothermal treatment leads to a gradual increase of the number of functional groups of GO. However, the number of desorbed groups is influenced by the WPA and PTDCA components. This research offers new insights into GO, WPA, and PTCDA interactions which can have useful implications for development of electrochemical supercapacitors.",
publisher = "Belgrade : Institute of Technical Sciences of SASA",
journal = "21st Young Researchers' Conference Materials Sciences and Engineering : program and the book of abstracts",
title = "Investigating the influence of hydrothermal treatment on oxygen functional groups in graphene oxide-based nanocomposites",
pages = "43-43",
url = "https://hdl.handle.net/21.15107/rcub_vinar_12316"
}

Pejčić, M., Mravik, Ž., Bajuk-Bogdanović, D., Grujičić, M., Rmuš Mravik, J., Jovanović, S.,& Jovanović, Z.. (2023). Investigating the influence of hydrothermal treatment on oxygen functional groups in graphene oxide-based nanocomposites. in 21st Young Researchers' Conference Materials Sciences and Engineering : program and the book of abstracts
Belgrade : Institute of Technical Sciences of SASA., 43-43.
https://hdl.handle.net/21.15107/rcub_vinar_12316

Pejčić M, Mravik Ž, Bajuk-Bogdanović D, Grujičić M, Rmuš Mravik J, Jovanović S, Jovanović Z. Investigating the influence of hydrothermal treatment on oxygen functional groups in graphene oxide-based nanocomposites. in 21st Young Researchers' Conference Materials Sciences and Engineering : program and the book of abstracts. 2023;:43-43.
https://hdl.handle.net/21.15107/rcub_vinar_12316 .

Pejčić, Milica, Mravik, Željko, Bajuk-Bogdanović, Danica, Grujičić, Marija, Rmuš Mravik, Jelena, Jovanović, Sonja, Jovanović, Zoran, "Investigating the influence of hydrothermal treatment on oxygen functional groups in graphene oxide-based nanocomposites" in 21st Young Researchers' Conference Materials Sciences and Engineering : program and the book of abstracts (2023):43-43,
https://hdl.handle.net/21.15107/rcub_vinar_12316 .

TY  - CONF
AU  - Jovanović, Zoran
AU  - Jovanović, Sonja
AU  - Mravik, Željko
AU  - Rmuš, Jelena
AU  - Jelić, Marko
AU  - Pejčić, Milica
AU  - Grujičić, Marija
AU  - Petković, Darija
PY  - 2023
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/12334
AB  - Elektrohemijska istraživanja su prethodnih godina dala ključni podstrek globalnim stremljenjima ka obnovljivim izvorima energije. Višegeneracijski napori, u početku motivisani željom za fundamentalnim razumevanjem procesa, aktuelizovani su očekivanim nedostatkom fosilnih goriva i pratećim nepovoljnim uticajem na životnu sredinu. Nanomaterijali su omogućili spektakularan skok u tehnološkim inovacijama i neosporan je njihov doprinos obnovljivim izvorima energije. Zahvaljujući novim svojstvima nanomaterijala i njihovoj sinergiji, omogućeno je dalje unapređenje i integracija različitih funkcionalnosti. Pri tome, postalo je jasno da atomski precizan dizajn materijala postaje kritičan za razvoj naprava sledeće generacije. Ovo je posebno važno u slučaju nanokompozita gde interakcija komponenti pojačava moguće sinergijske doprinose. U izlaganju će biti dat osvrt na napredne metode sinteze i modifikacije materijala – od tradicionalnih, do tankih filmova, 0D i 2D nanomaterijala i njihovih kompozita – posmatranih kroz prizmu obnovljivih izvora energije i održivosti (elektrohemijski superkondenzatori, razgradnja vode, senzori, i dr.). Razvoj novih materijala i unapređenje elektrohemijskih sistema ima potencijal da suštinski učini obnovljivu energiju održivijom i dostupnijom, time otvarajući put ka održivoj budućnosti.
C3  - Savremena stremljenja u elektrohemiji u proceu prelaska na obnovljive izvore energije: Naučni skup posvećen 100 - godišnjici rođenja inostranog člana SANU Dž. O'M. Bokrisa : Knjiga izvoda
T1  - Sinteza i modifikacija naprednih nanomaterijala - pogled kroz prizmu obnovljivih izvora energije
SP  - 19
EP  - 19
UR  - https://hdl.handle.net/21.15107/rcub_vinar_12334
ER  - 

@conference{
author = "Jovanović, Zoran and Jovanović, Sonja and Mravik, Željko and Rmuš, Jelena and Jelić, Marko and Pejčić, Milica and Grujičić, Marija and Petković, Darija",
year = "2023",
abstract = "Elektrohemijska istraživanja su prethodnih godina dala ključni podstrek globalnim stremljenjima ka obnovljivim izvorima energije. Višegeneracijski napori, u početku motivisani željom za fundamentalnim razumevanjem procesa, aktuelizovani su očekivanim nedostatkom fosilnih goriva i pratećim nepovoljnim uticajem na životnu sredinu. Nanomaterijali su omogućili spektakularan skok u tehnološkim inovacijama i neosporan je njihov doprinos obnovljivim izvorima energije. Zahvaljujući novim svojstvima nanomaterijala i njihovoj sinergiji, omogućeno je dalje unapređenje i integracija različitih funkcionalnosti. Pri tome, postalo je jasno da atomski precizan dizajn materijala postaje kritičan za razvoj naprava sledeće generacije. Ovo je posebno važno u slučaju nanokompozita gde interakcija komponenti pojačava moguće sinergijske doprinose. U izlaganju će biti dat osvrt na napredne metode sinteze i modifikacije materijala – od tradicionalnih, do tankih filmova, 0D i 2D nanomaterijala i njihovih kompozita – posmatranih kroz prizmu obnovljivih izvora energije i održivosti (elektrohemijski superkondenzatori, razgradnja vode, senzori, i dr.). Razvoj novih materijala i unapređenje elektrohemijskih sistema ima potencijal da suštinski učini obnovljivu energiju održivijom i dostupnijom, time otvarajući put ka održivoj budućnosti.",
journal = "Savremena stremljenja u elektrohemiji u proceu prelaska na obnovljive izvore energije: Naučni skup posvećen 100 - godišnjici rođenja inostranog člana SANU Dž. O'M. Bokrisa : Knjiga izvoda",
title = "Sinteza i modifikacija naprednih nanomaterijala - pogled kroz prizmu obnovljivih izvora energije",
pages = "19-19",
url = "https://hdl.handle.net/21.15107/rcub_vinar_12334"
}

Jovanović, Z., Jovanović, S., Mravik, Ž., Rmuš, J., Jelić, M., Pejčić, M., Grujičić, M.,& Petković, D.. (2023). Sinteza i modifikacija naprednih nanomaterijala - pogled kroz prizmu obnovljivih izvora energije. in Savremena stremljenja u elektrohemiji u proceu prelaska na obnovljive izvore energije: Naučni skup posvećen 100 - godišnjici rođenja inostranog člana SANU Dž. O'M. Bokrisa : Knjiga izvoda, 19-19.
https://hdl.handle.net/21.15107/rcub_vinar_12334

Jovanović Z, Jovanović S, Mravik Ž, Rmuš J, Jelić M, Pejčić M, Grujičić M, Petković D. Sinteza i modifikacija naprednih nanomaterijala - pogled kroz prizmu obnovljivih izvora energije. in Savremena stremljenja u elektrohemiji u proceu prelaska na obnovljive izvore energije: Naučni skup posvećen 100 - godišnjici rođenja inostranog člana SANU Dž. O'M. Bokrisa : Knjiga izvoda. 2023;:19-19.
https://hdl.handle.net/21.15107/rcub_vinar_12334 .

Jovanović, Zoran, Jovanović, Sonja, Mravik, Željko, Rmuš, Jelena, Jelić, Marko, Pejčić, Milica, Grujičić, Marija, Petković, Darija, "Sinteza i modifikacija naprednih nanomaterijala - pogled kroz prizmu obnovljivih izvora energije" in Savremena stremljenja u elektrohemiji u proceu prelaska na obnovljive izvore energije: Naučni skup posvećen 100 - godišnjici rođenja inostranog člana SANU Dž. O'M. Bokrisa : Knjiga izvoda (2023):19-19,
https://hdl.handle.net/21.15107/rcub_vinar_12334 .

TY  - CONF
AU  - Grujičić, Marija
AU  - Jelić, Marko
AU  - Stojković Simatović, Ivana
AU  - Bajuk Bogdanović, Danica
AU  - Petković, Darija
AU  - Jovanović, Zoran
AU  - Jovanović, Sonja
PY  - 2023
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/12317
AB  - In this study, solvothermally synthesized nanoparticles of cobalt ferrite (CoFe2O4, CFO) and Zn/Ga-dopped cobalt ferrite (Co0.5Zn0.5Fe2O4, CFO_Zn and CoFe1.5Ga0.5O4, CFO_Ga, respectively) with dihydrocaffeic acid (DHCA) as a surfactant were examined for electrochemical detection of gallic acid. Based on X-ray diffraction analysis, diffraction maxima of all samples correspond to the cubic spinel phase, while transmission electron microscopy showed that the nanoparticles are non-agglomerated, sphere-like with an average size of 5±1 nm. The presence of DHCA on the surface of nanoparticles was confirmed by Fourier Transform Infrared Spectroscopy (FTIR). For the purpose of electrochemical detection of gallic acid the modified glassy carbon electrode (m-GCE) was prepared from CFO, CFO_Zn and CFO_Ga nanoparticles. Initial tests have shown instability/disintegration of m-GCE in aqueous solutions, because of which samples were annealed at 450 °C in air. Cyclic voltammograms of all annealed samples showed good reversibility in the system [Fe(CN)6] 3-/4- . The most efficient electron transfer was achieved when the mass ratio between sample and Nafion® was 85:15, respectively. The best sensitivity to gallic acid (10-4 M, in Britton-Robinson buffer) was observed for CFO_Zn sample. Results are showing that by selective functionalization and surface modification of nanoparticles, it is possible to optimize the electrochemical properties suitable for sensing, which is the basis of this method and the goal of further research.
PB  - Belgrade : Institute of Technical Sciences of SASA
C3  - 21st Young Researchers' Conference Materials Sciences and Engineering : program and the book of abstracts
T1  - Enhanced electrochemical detection of gallic acid using modified glassy carbon electrodes with Zn/Ga-dopped cobalt ferrite
SP  - 44
EP  - 44
UR  - https://hdl.handle.net/21.15107/rcub_vinar_12317
ER  - 

@conference{
author = "Grujičić, Marija and Jelić, Marko and Stojković Simatović, Ivana and Bajuk Bogdanović, Danica and Petković, Darija and Jovanović, Zoran and Jovanović, Sonja",
year = "2023",
abstract = "In this study, solvothermally synthesized nanoparticles of cobalt ferrite (CoFe2O4, CFO) and Zn/Ga-dopped cobalt ferrite (Co0.5Zn0.5Fe2O4, CFO_Zn and CoFe1.5Ga0.5O4, CFO_Ga, respectively) with dihydrocaffeic acid (DHCA) as a surfactant were examined for electrochemical detection of gallic acid. Based on X-ray diffraction analysis, diffraction maxima of all samples correspond to the cubic spinel phase, while transmission electron microscopy showed that the nanoparticles are non-agglomerated, sphere-like with an average size of 5±1 nm. The presence of DHCA on the surface of nanoparticles was confirmed by Fourier Transform Infrared Spectroscopy (FTIR). For the purpose of electrochemical detection of gallic acid the modified glassy carbon electrode (m-GCE) was prepared from CFO, CFO_Zn and CFO_Ga nanoparticles. Initial tests have shown instability/disintegration of m-GCE in aqueous solutions, because of which samples were annealed at 450 °C in air. Cyclic voltammograms of all annealed samples showed good reversibility in the system [Fe(CN)6] 3-/4- . The most efficient electron transfer was achieved when the mass ratio between sample and Nafion® was 85:15, respectively. The best sensitivity to gallic acid (10-4 M, in Britton-Robinson buffer) was observed for CFO_Zn sample. Results are showing that by selective functionalization and surface modification of nanoparticles, it is possible to optimize the electrochemical properties suitable for sensing, which is the basis of this method and the goal of further research.",
publisher = "Belgrade : Institute of Technical Sciences of SASA",
journal = "21st Young Researchers' Conference Materials Sciences and Engineering : program and the book of abstracts",
title = "Enhanced electrochemical detection of gallic acid using modified glassy carbon electrodes with Zn/Ga-dopped cobalt ferrite",
pages = "44-44",
url = "https://hdl.handle.net/21.15107/rcub_vinar_12317"
}

Grujičić, M., Jelić, M., Stojković Simatović, I., Bajuk Bogdanović, D., Petković, D., Jovanović, Z.,& Jovanović, S.. (2023). Enhanced electrochemical detection of gallic acid using modified glassy carbon electrodes with Zn/Ga-dopped cobalt ferrite. in 21st Young Researchers' Conference Materials Sciences and Engineering : program and the book of abstracts
Belgrade : Institute of Technical Sciences of SASA., 44-44.
https://hdl.handle.net/21.15107/rcub_vinar_12317

Grujičić M, Jelić M, Stojković Simatović I, Bajuk Bogdanović D, Petković D, Jovanović Z, Jovanović S. Enhanced electrochemical detection of gallic acid using modified glassy carbon electrodes with Zn/Ga-dopped cobalt ferrite. in 21st Young Researchers' Conference Materials Sciences and Engineering : program and the book of abstracts. 2023;:44-44.
https://hdl.handle.net/21.15107/rcub_vinar_12317 .

Grujičić, Marija, Jelić, Marko, Stojković Simatović, Ivana, Bajuk Bogdanović, Danica, Petković, Darija, Jovanović, Zoran, Jovanović, Sonja, "Enhanced electrochemical detection of gallic acid using modified glassy carbon electrodes with Zn/Ga-dopped cobalt ferrite" in 21st Young Researchers' Conference Materials Sciences and Engineering : program and the book of abstracts (2023):44-44,
https://hdl.handle.net/21.15107/rcub_vinar_12317 .

TY  - JOUR
AU  - Grujičić, Marija
AU  - Mravik, Željko
AU  - Bajuk-Bogdanović, Danica
AU  - Vengust, Damjan
AU  - Jovanović, Zoran M.
AU  - Stojković Simatović, Ivana
AU  - Jovanović, Sonja
PY  - 2022
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/12756
AB  - U ovom radu prikazana su elektrohemijska svojstva kompozita grafen-oksida i nanočestica kobalt-ferita, kao i kobalt-ferita dopiranog sa cinkom i galijumom. Grafen-oksid (GO) sintetisan je modifikovanom Hamerovom metodom. Magnetne nanočestice sintetisane su solvotermalnom metodom, nakon čega je izvršena izmena oleinske kiseline dihidrokofeinskom kiselinom sa ciljem dobijanja hidrofilnog materijala. Kompoziti grafen-oksida i magnetnih nanočestica sintetisani su hidrotermalnom metodom, prilikom čega je udeo magnetnih čestica bio 5 i 15 težinskih % u odnosu na grafen-oksid. Rezultati rendgeno-strukturne i FTIR analize potvrdili su potpunu oksidaciju grafenskih slojeva. SEM i TEM analize pokazale su depoziciju magnetnih nanočestica na sloju grafen-oksida, bez promene veličine ili oblika nanočestica. FTIR analiza hidrotemalno tretiranog grafen-oksida i kompozita pokazala je da dolazi do delimične redukcije epoksi grupa, kao i da se uspostavlja vodonična veza između komponenti kompozita. Ciklovoltamogrami pokazuju da su kompoziti stabilni pri brzinama polarizacije od 5 do 400 mV s-1, kao i da je njihov kapacitet pretežno pseudokapacitivne prirode. Pseudokapacitivnost potiče od oksidoredukcionih reakcija H+ jona iz elektrolita i površinskih funkcionalnih grupa grafen oksida. Na osnovu ciklovoltamograma izračunati su specifični kapaciteti svih kompozita, pri čemu je najveću vrednost pokazao kompozit CFO_GO_15% koja iznosi 36,86 F g-1 pri brzini polarizacije od 5 mV s-1.
AB  - This paper presents the electrochemical properties of graphene-oxide composites and nanoparticles of cobalt-ferrite, as well as cobalt-ferrite doped with zinc and gallium. Graphene-oxide (GO) was synthesized by a modified Hummer's method. The magnetic nanoparticles were synthesized by the solvothermal method, after which the oleic acid was exchanged with dihydrocaffeic acid to obtain the hydrophilic material. Composites of graphene-oxide and magnetic nanoparticles were synthesized by the hydrothermal method, where the share of magnetic particles was 5 and 15 wt.% on graphene-oxide. The results of X-ray structural and FTIR analysis confirmed the complete oxidation of graphene layers. SEM and TEM analyzes showed deposition of magnetic nanoparticles on the graphene-oxide layer, without changing the size or shape of the nanoparticles. FTIR analysis of hydrothermally treated graphene oxide and composites showed that there is a partial reduction of epoxy groups, also a hydrogen bond is established between the components of the composite. Cyclic voltammograms show that the composites are stable at polarization rates of 5-400 mV s-1, and that their capacity is predominantly pseudocapacitive in nature. Pseudocapacitance originates from the oxidoreduction reactions of H+ ions from electrolytes and surface functional groups of graphene-oxide. Based on the cyclic voltammograms, the specific capacities of all composites were calculated and the highest value being shown by the CFO_GO_15% composite, which is 36.86 F g-1 at a polarization rate of 5 mV s-1.
T2  - Tehnika
T1  - Elektrohemijska svojstva kompozita grafen-oksida i kobalt-ferita dopiranog cinkom i galijumom
T1  - Electrochemical properties of composites of graphene-oxide and cobalt-ferrite doped with zink and gallium
VL  - 77
IS  - 2
SP  - 155
EP  - 162
DO  - 10.5937/tehnika2202155G
ER  - 

@article{
author = "Grujičić, Marija and Mravik, Željko and Bajuk-Bogdanović, Danica and Vengust, Damjan and Jovanović, Zoran M. and Stojković Simatović, Ivana and Jovanović, Sonja",
year = "2022",
abstract = "U ovom radu prikazana su elektrohemijska svojstva kompozita grafen-oksida i nanočestica kobalt-ferita, kao i kobalt-ferita dopiranog sa cinkom i galijumom. Grafen-oksid (GO) sintetisan je modifikovanom Hamerovom metodom. Magnetne nanočestice sintetisane su solvotermalnom metodom, nakon čega je izvršena izmena oleinske kiseline dihidrokofeinskom kiselinom sa ciljem dobijanja hidrofilnog materijala. Kompoziti grafen-oksida i magnetnih nanočestica sintetisani su hidrotermalnom metodom, prilikom čega je udeo magnetnih čestica bio 5 i 15 težinskih % u odnosu na grafen-oksid. Rezultati rendgeno-strukturne i FTIR analize potvrdili su potpunu oksidaciju grafenskih slojeva. SEM i TEM analize pokazale su depoziciju magnetnih nanočestica na sloju grafen-oksida, bez promene veličine ili oblika nanočestica. FTIR analiza hidrotemalno tretiranog grafen-oksida i kompozita pokazala je da dolazi do delimične redukcije epoksi grupa, kao i da se uspostavlja vodonična veza između komponenti kompozita. Ciklovoltamogrami pokazuju da su kompoziti stabilni pri brzinama polarizacije od 5 do 400 mV s-1, kao i da je njihov kapacitet pretežno pseudokapacitivne prirode. Pseudokapacitivnost potiče od oksidoredukcionih reakcija H+ jona iz elektrolita i površinskih funkcionalnih grupa grafen oksida. Na osnovu ciklovoltamograma izračunati su specifični kapaciteti svih kompozita, pri čemu je najveću vrednost pokazao kompozit CFO_GO_15% koja iznosi 36,86 F g-1 pri brzini polarizacije od 5 mV s-1., This paper presents the electrochemical properties of graphene-oxide composites and nanoparticles of cobalt-ferrite, as well as cobalt-ferrite doped with zinc and gallium. Graphene-oxide (GO) was synthesized by a modified Hummer's method. The magnetic nanoparticles were synthesized by the solvothermal method, after which the oleic acid was exchanged with dihydrocaffeic acid to obtain the hydrophilic material. Composites of graphene-oxide and magnetic nanoparticles were synthesized by the hydrothermal method, where the share of magnetic particles was 5 and 15 wt.% on graphene-oxide. The results of X-ray structural and FTIR analysis confirmed the complete oxidation of graphene layers. SEM and TEM analyzes showed deposition of magnetic nanoparticles on the graphene-oxide layer, without changing the size or shape of the nanoparticles. FTIR analysis of hydrothermally treated graphene oxide and composites showed that there is a partial reduction of epoxy groups, also a hydrogen bond is established between the components of the composite. Cyclic voltammograms show that the composites are stable at polarization rates of 5-400 mV s-1, and that their capacity is predominantly pseudocapacitive in nature. Pseudocapacitance originates from the oxidoreduction reactions of H+ ions from electrolytes and surface functional groups of graphene-oxide. Based on the cyclic voltammograms, the specific capacities of all composites were calculated and the highest value being shown by the CFO_GO_15% composite, which is 36.86 F g-1 at a polarization rate of 5 mV s-1.",
journal = "Tehnika",
title = "Elektrohemijska svojstva kompozita grafen-oksida i kobalt-ferita dopiranog cinkom i galijumom, Electrochemical properties of composites of graphene-oxide and cobalt-ferrite doped with zink and gallium",
volume = "77",
number = "2",
pages = "155-162",
doi = "10.5937/tehnika2202155G"
}

Grujičić, M., Mravik, Ž., Bajuk-Bogdanović, D., Vengust, D., Jovanović, Z. M., Stojković Simatović, I.,& Jovanović, S.. (2022). Elektrohemijska svojstva kompozita grafen-oksida i kobalt-ferita dopiranog cinkom i galijumom. in Tehnika, 77(2), 155-162.
https://doi.org/10.5937/tehnika2202155G

Grujičić M, Mravik Ž, Bajuk-Bogdanović D, Vengust D, Jovanović ZM, Stojković Simatović I, Jovanović S. Elektrohemijska svojstva kompozita grafen-oksida i kobalt-ferita dopiranog cinkom i galijumom. in Tehnika. 2022;77(2):155-162.
doi:10.5937/tehnika2202155G .

Grujičić, Marija, Mravik, Željko, Bajuk-Bogdanović, Danica, Vengust, Damjan, Jovanović, Zoran M., Stojković Simatović, Ivana, Jovanović, Sonja, "Elektrohemijska svojstva kompozita grafen-oksida i kobalt-ferita dopiranog cinkom i galijumom" in Tehnika, 77, no. 2 (2022):155-162,
https://doi.org/10.5937/tehnika2202155G . .

TY  - CONF
AU  - Grujičić, Marija
AU  - Mravik, Željko
AU  - Bajuk-Bogdanović, Danica
AU  - Vengust, Damjan
AU  - Jovanović, Zoran
AU  - Stojković Simatović, Ivana
AU  - Jovanović, Sonja
PY  - 2022
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/12757
AB  - The possibility of surface functionalization and formation of stable aqueous suspensions make graphene oxide (GO) suitable as base for composite materials, especially with nanoparticles. Cobalt ferrite (CFO) has attracted attention due to its unique properties such as large magnetic anisotropy, high coercivity, moderate saturation magnetization, excellent chemical stability, mechanical hardness, etc. This study presents the electrochemical properties of GO and CFO composites, as well as CFO doped with zinc (CFO_Zn) and gallium (CFO_Ga). Magnetic nanoparticles were synthesized using the solvothermal method, after which the oleic acid was exchanged with dihydrocaffeic acid to obtain the hydrophilic material. GO was synthesized using a modified Hummer's method. Composites of GO and magnetic nanoparticles were synthesized by the hydrothermal method (T = 120 °C, t = 3 h), with nominal fractions of 5 and 15 wt.% of magnetic nanoparticles. X-ray structural diffraction, as well as FTIR analysis, confirmed the complete oxidation of graphene layers. SEM and TEM images showed deposition of magnetic nanoparticles on GO layer with the different distribution density between 5 wt.% and 15 wt.% composites. Also, shape and size of magnetic nanoparticles remained unchanged. Based on FTIR analysis of hydrothermally treated GO and composites a partial reduction of epoxy groups was found along with hydrogen bond established between the components of the composite. The electrochemical charge storage of composites is mainly of pseudocapacitive nature, which originates from the oxidoreduction reactions of H+ ions from electrolytes and surface functional groups of GO. The best electrochemical properties, in terms of the highest specific capacity, were shown by the composite which contains 15 wt.% CFO, which value is 36.86 F g-1 at a polarization rate of 5 mV s-1
PB  - Belgrade : Materials Research Society of Serbia – MRS-Serbia
C3  - 23rd annual conference - YUCOMAT 2022 & 12th World Round Table Conference on Sintering - WRTCS 2022 : Program and Book of Abstracts
T1  - Electrochemical properties of composites of graphene oxide and cobalt ferrite doped with zink and gallium
VL  - XLV
SP  - 135
EP  - 135
UR  - https://hdl.handle.net/21.15107/rcub_vinar_12757
ER  - 

@conference{
author = "Grujičić, Marija and Mravik, Željko and Bajuk-Bogdanović, Danica and Vengust, Damjan and Jovanović, Zoran and Stojković Simatović, Ivana and Jovanović, Sonja",
year = "2022",
abstract = "The possibility of surface functionalization and formation of stable aqueous suspensions make graphene oxide (GO) suitable as base for composite materials, especially with nanoparticles. Cobalt ferrite (CFO) has attracted attention due to its unique properties such as large magnetic anisotropy, high coercivity, moderate saturation magnetization, excellent chemical stability, mechanical hardness, etc. This study presents the electrochemical properties of GO and CFO composites, as well as CFO doped with zinc (CFO_Zn) and gallium (CFO_Ga). Magnetic nanoparticles were synthesized using the solvothermal method, after which the oleic acid was exchanged with dihydrocaffeic acid to obtain the hydrophilic material. GO was synthesized using a modified Hummer's method. Composites of GO and magnetic nanoparticles were synthesized by the hydrothermal method (T = 120 °C, t = 3 h), with nominal fractions of 5 and 15 wt.% of magnetic nanoparticles. X-ray structural diffraction, as well as FTIR analysis, confirmed the complete oxidation of graphene layers. SEM and TEM images showed deposition of magnetic nanoparticles on GO layer with the different distribution density between 5 wt.% and 15 wt.% composites. Also, shape and size of magnetic nanoparticles remained unchanged. Based on FTIR analysis of hydrothermally treated GO and composites a partial reduction of epoxy groups was found along with hydrogen bond established between the components of the composite. The electrochemical charge storage of composites is mainly of pseudocapacitive nature, which originates from the oxidoreduction reactions of H+ ions from electrolytes and surface functional groups of GO. The best electrochemical properties, in terms of the highest specific capacity, were shown by the composite which contains 15 wt.% CFO, which value is 36.86 F g-1 at a polarization rate of 5 mV s-1",
publisher = "Belgrade : Materials Research Society of Serbia – MRS-Serbia",
journal = "23rd annual conference - YUCOMAT 2022 & 12th World Round Table Conference on Sintering - WRTCS 2022 : Program and Book of Abstracts",
title = "Electrochemical properties of composites of graphene oxide and cobalt ferrite doped with zink and gallium",
volume = "XLV",
pages = "135-135",
url = "https://hdl.handle.net/21.15107/rcub_vinar_12757"
}

Grujičić, M., Mravik, Ž., Bajuk-Bogdanović, D., Vengust, D., Jovanović, Z., Stojković Simatović, I.,& Jovanović, S.. (2022). Electrochemical properties of composites of graphene oxide and cobalt ferrite doped with zink and gallium. in 23rd annual conference - YUCOMAT 2022 & 12th World Round Table Conference on Sintering - WRTCS 2022 : Program and Book of Abstracts
Belgrade : Materials Research Society of Serbia – MRS-Serbia., XLV, 135-135.
https://hdl.handle.net/21.15107/rcub_vinar_12757

Grujičić M, Mravik Ž, Bajuk-Bogdanović D, Vengust D, Jovanović Z, Stojković Simatović I, Jovanović S. Electrochemical properties of composites of graphene oxide and cobalt ferrite doped with zink and gallium. in 23rd annual conference - YUCOMAT 2022 & 12th World Round Table Conference on Sintering - WRTCS 2022 : Program and Book of Abstracts. 2022;XLV:135-135.
https://hdl.handle.net/21.15107/rcub_vinar_12757 .

Grujičić, Marija, Mravik, Željko, Bajuk-Bogdanović, Danica, Vengust, Damjan, Jovanović, Zoran, Stojković Simatović, Ivana, Jovanović, Sonja, "Electrochemical properties of composites of graphene oxide and cobalt ferrite doped with zink and gallium" in 23rd annual conference - YUCOMAT 2022 & 12th World Round Table Conference on Sintering - WRTCS 2022 : Program and Book of Abstracts, XLV (2022):135-135,
https://hdl.handle.net/21.15107/rcub_vinar_12757 .

TY  - CONF
AU  - Jovanović, Sonja
AU  - Grujičić, Marija
AU  - Jelić, Marko
AU  - Vukomanović, Marija
AU  - Spreitzer, Matjaž
AU  - Maček-Kržmanc, Marjeta
AU  - Peddis, Davide
PY  - 2022
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/12297
AB  - In the last two decades, cobalt ferrite (CoFe2O4, CFO) has attracted extensive attention due to its applicability in data storage, catalysis, energy, environment, and in particular, biomedicine. To further extend applicability and improve understanding of fundamental processes, the present work investigates the influence of heteroatoms on physicochemical properties of CFO. Solvothermal method was used for designing a non-agglomerated particles with uniform morpho-structural properties. The physicochemical properties of Zn2+ and Ga3+ substituted CFO nanoparticles were examined (Co(1-x)ZnxFe2O4 and CoGaxFe(2-x)O4; x=0, 0.1, 0.3 and 0.5). In order to isolate the contribution of heteroatoms, the synthesis condition were optimized to allow preparation of nonagglomerated particles with the narrow particle size and shape distribution, including the constant amount of capping agent. The X-ray diffraction (XRD) measurements confirmed the presence of pure cubic spinel phase in all samples, while the transmission electron microscopy (TEM) showed sphere-like nanoparticles with a mean diameter of 6±1 nm. The amount of adsorbed oleic acid on the surface of the nanoparticles, determined by thermogravimetric (TG) analysis, is 22-28 %, which indicates the formation of a complete monolayer of surfactant. The FT-IR analysis substantiated the presence of oleic acid on the surface of the nanoparticles and discovered its covalent bonding to the metal atoms. Substitution of host-atoms was also confirmed by Raman spectroscopy. Magnetic measurements revealed the influence of heteroatoms on saturation magnetization and magnetic anisotropy, showing for all the samples superparamagnetic behavior at room temperature. The substitution of Co2+ and Fe3+ ions with Zn2+ and Ga3+, respectively, leads to the change in chemical composition and cationic distribution of CFO and consequently to variation of its magnetic properties that can be tuned for different applications.
PB  - Belgrade : Vinča Institute of Nuclear Sciences - National Institute of thе Republic of Serbia, University of Belgrade
PB  - Belgrade : Serbian Society for Innovative Materials in Extreme Conditions (SIM-EXTREME)
C3  - IMEC 2022 : 1st Intentational conference on innovativ materials in extreme conditions : Program and Book of abstracts
T1  - Solvothermal synthesis of zinc- and gallium-substituted cobalt ferrite nanoparticles
SP  - 57
EP  - 57
UR  - https://hdl.handle.net/21.15107/rcub_vinar_12297
ER  - 

@conference{
author = "Jovanović, Sonja and Grujičić, Marija and Jelić, Marko and Vukomanović, Marija and Spreitzer, Matjaž and Maček-Kržmanc, Marjeta and Peddis, Davide",
year = "2022",
abstract = "In the last two decades, cobalt ferrite (CoFe2O4, CFO) has attracted extensive attention due to its applicability in data storage, catalysis, energy, environment, and in particular, biomedicine. To further extend applicability and improve understanding of fundamental processes, the present work investigates the influence of heteroatoms on physicochemical properties of CFO. Solvothermal method was used for designing a non-agglomerated particles with uniform morpho-structural properties. The physicochemical properties of Zn2+ and Ga3+ substituted CFO nanoparticles were examined (Co(1-x)ZnxFe2O4 and CoGaxFe(2-x)O4; x=0, 0.1, 0.3 and 0.5). In order to isolate the contribution of heteroatoms, the synthesis condition were optimized to allow preparation of nonagglomerated particles with the narrow particle size and shape distribution, including the constant amount of capping agent. The X-ray diffraction (XRD) measurements confirmed the presence of pure cubic spinel phase in all samples, while the transmission electron microscopy (TEM) showed sphere-like nanoparticles with a mean diameter of 6±1 nm. The amount of adsorbed oleic acid on the surface of the nanoparticles, determined by thermogravimetric (TG) analysis, is 22-28 %, which indicates the formation of a complete monolayer of surfactant. The FT-IR analysis substantiated the presence of oleic acid on the surface of the nanoparticles and discovered its covalent bonding to the metal atoms. Substitution of host-atoms was also confirmed by Raman spectroscopy. Magnetic measurements revealed the influence of heteroatoms on saturation magnetization and magnetic anisotropy, showing for all the samples superparamagnetic behavior at room temperature. The substitution of Co2+ and Fe3+ ions with Zn2+ and Ga3+, respectively, leads to the change in chemical composition and cationic distribution of CFO and consequently to variation of its magnetic properties that can be tuned for different applications.",
publisher = "Belgrade : Vinča Institute of Nuclear Sciences - National Institute of thе Republic of Serbia, University of Belgrade, Belgrade : Serbian Society for Innovative Materials in Extreme Conditions (SIM-EXTREME)",
journal = "IMEC 2022 : 1st Intentational conference on innovativ materials in extreme conditions : Program and Book of abstracts",
title = "Solvothermal synthesis of zinc- and gallium-substituted cobalt ferrite nanoparticles",
pages = "57-57",
url = "https://hdl.handle.net/21.15107/rcub_vinar_12297"
}

Jovanović, S., Grujičić, M., Jelić, M., Vukomanović, M., Spreitzer, M., Maček-Kržmanc, M.,& Peddis, D.. (2022). Solvothermal synthesis of zinc- and gallium-substituted cobalt ferrite nanoparticles. in IMEC 2022 : 1st Intentational conference on innovativ materials in extreme conditions : Program and Book of abstracts
Belgrade : Vinča Institute of Nuclear Sciences - National Institute of thе Republic of Serbia, University of Belgrade., 57-57.
https://hdl.handle.net/21.15107/rcub_vinar_12297

Jovanović S, Grujičić M, Jelić M, Vukomanović M, Spreitzer M, Maček-Kržmanc M, Peddis D. Solvothermal synthesis of zinc- and gallium-substituted cobalt ferrite nanoparticles. in IMEC 2022 : 1st Intentational conference on innovativ materials in extreme conditions : Program and Book of abstracts. 2022;:57-57.
https://hdl.handle.net/21.15107/rcub_vinar_12297 .

Jovanović, Sonja, Grujičić, Marija, Jelić, Marko, Vukomanović, Marija, Spreitzer, Matjaž, Maček-Kržmanc, Marjeta, Peddis, Davide, "Solvothermal synthesis of zinc- and gallium-substituted cobalt ferrite nanoparticles" in IMEC 2022 : 1st Intentational conference on innovativ materials in extreme conditions : Program and Book of abstracts (2022):57-57,
https://hdl.handle.net/21.15107/rcub_vinar_12297 .

TY  - CONF
AU  - Grujičić, Marija
AU  - Stojković Simatović, Ivana
AU  - Bajuk-Bogdanović, Danica
AU  - Jovanović, Zoran
AU  - Mravik, Željko
AU  - Jovanović, Sonja
PY  - 2021
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/12711
AB  - In this paper, the physicochemical properties of nanocomposites of graphene oxide (GO) and cobalt ferrite nanoparticles CFO NPs (pristine and doped with zinc and gallium, CFO_Zn, CFO_Ga) were investigated. CFO, CFO_Zn and CFO_Ga NPs were synthesized using the solvothermal method with oleic acid (OA) as a surfactant. X-ray diffraction (XRD) confirmed the presence of pure ferrite phase while transmission electron microscopy (TEM) revealed spherical and non-agglomerated NPs with average size of 5±1 nm. Fourier transform infrared spectroscopy (FTIR) has confirmed bridging bidentate interaction between the oleic acid and the metal atoms on the surface of the NPs, while Raman spectroscopy results confirmed the incorporation of zinc and gallium in the spinel structure. Prior to preparation of nanocomposite with GO, an OA coating has been exchanged with dihydrocaffeic acid (DHCA). DHCA binds to surface of NPs through both covalent bridging bidentate interaction and catechol groups, as determined by FTIR. Nanocomposite has been obtained by adding CFO(_Zn/Ga) NPs to a GO suspension with nominal fractions of 5 to 15 wt.%, followed by homogenization and hydrothermal treatment (T=120 °C, t=3 h). TEM results revealed that the shape and size of NPs remain unchanged in nanocomposite, while FTIR results have shown that hydrogen bond is established between the functional groups of GO and DHCA. Electrochemical properties of individual components and nanocomposite were examined by cyclic voltammetry. The best electrochemical properties, in terms of the highest specific capacity, were shown by the composite which contains 15 wt.% CFO NPs.
PB  - Belgrade : Institute of Technical Sciences of SASA
C3  - 19th Young Researchers’ Conference - Materials Science and Engineering : Program and the Book of Abstracts
T1  - Surface, structural and electric properties of ion beam irradiated graphene oxide papers
SP  - 39
EP  - 39
UR  - https://hdl.handle.net/21.15107/rcub_vinar_12711
ER  - 

@conference{
author = "Grujičić, Marija and Stojković Simatović, Ivana and Bajuk-Bogdanović, Danica and Jovanović, Zoran and Mravik, Željko and Jovanović, Sonja",
year = "2021",
abstract = "In this paper, the physicochemical properties of nanocomposites of graphene oxide (GO) and cobalt ferrite nanoparticles CFO NPs (pristine and doped with zinc and gallium, CFO_Zn, CFO_Ga) were investigated. CFO, CFO_Zn and CFO_Ga NPs were synthesized using the solvothermal method with oleic acid (OA) as a surfactant. X-ray diffraction (XRD) confirmed the presence of pure ferrite phase while transmission electron microscopy (TEM) revealed spherical and non-agglomerated NPs with average size of 5±1 nm. Fourier transform infrared spectroscopy (FTIR) has confirmed bridging bidentate interaction between the oleic acid and the metal atoms on the surface of the NPs, while Raman spectroscopy results confirmed the incorporation of zinc and gallium in the spinel structure. Prior to preparation of nanocomposite with GO, an OA coating has been exchanged with dihydrocaffeic acid (DHCA). DHCA binds to surface of NPs through both covalent bridging bidentate interaction and catechol groups, as determined by FTIR. Nanocomposite has been obtained by adding CFO(_Zn/Ga) NPs to a GO suspension with nominal fractions of 5 to 15 wt.%, followed by homogenization and hydrothermal treatment (T=120 °C, t=3 h). TEM results revealed that the shape and size of NPs remain unchanged in nanocomposite, while FTIR results have shown that hydrogen bond is established between the functional groups of GO and DHCA. Electrochemical properties of individual components and nanocomposite were examined by cyclic voltammetry. The best electrochemical properties, in terms of the highest specific capacity, were shown by the composite which contains 15 wt.% CFO NPs.",
publisher = "Belgrade : Institute of Technical Sciences of SASA",
journal = "19th Young Researchers’ Conference - Materials Science and Engineering : Program and the Book of Abstracts",
title = "Surface, structural and electric properties of ion beam irradiated graphene oxide papers",
pages = "39-39",
url = "https://hdl.handle.net/21.15107/rcub_vinar_12711"
}

Grujičić, M., Stojković Simatović, I., Bajuk-Bogdanović, D., Jovanović, Z., Mravik, Ž.,& Jovanović, S.. (2021). Surface, structural and electric properties of ion beam irradiated graphene oxide papers. in 19th Young Researchers’ Conference - Materials Science and Engineering : Program and the Book of Abstracts
Belgrade : Institute of Technical Sciences of SASA., 39-39.
https://hdl.handle.net/21.15107/rcub_vinar_12711

Grujičić M, Stojković Simatović I, Bajuk-Bogdanović D, Jovanović Z, Mravik Ž, Jovanović S. Surface, structural and electric properties of ion beam irradiated graphene oxide papers. in 19th Young Researchers’ Conference - Materials Science and Engineering : Program and the Book of Abstracts. 2021;:39-39.
https://hdl.handle.net/21.15107/rcub_vinar_12711 .

Grujičić, Marija, Stojković Simatović, Ivana, Bajuk-Bogdanović, Danica, Jovanović, Zoran, Mravik, Željko, Jovanović, Sonja, "Surface, structural and electric properties of ion beam irradiated graphene oxide papers" in 19th Young Researchers’ Conference - Materials Science and Engineering : Program and the Book of Abstracts (2021):39-39,
https://hdl.handle.net/21.15107/rcub_vinar_12711 .

TY  - CONF
AU  - Jovanović, Sonja
AU  - Vukomanović, Marija
AU  - Spreitzer, Matjaž
AU  - Jovanović, Zoran
AU  - Maček- Kržmanc, Marjeta
AU  - Grujičić, Marija
AU  - Peddis, Davide
PY  - 2021
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/12532
AB  - In the last two decades, cobalt ferrite (CoFe2O4, CFO) has attracted extensive attention due to its applicability in data storage, catalysis, energy, environment, and in particular, biomedicine. To further extend applicability and improve understanding of fundamental processes, the present work investigates the influence of heteroatoms on physicochemical properties of CFO. Solvothermal method was used for designing a non-agglomerated particles with uniform morpho-structural properties. The physicochemical properties of Zn2+ and Ga3+ substituted CFO nanoparticles were examined (Co(1-x)ZnxFe2O4 and CoGaxFe(2-x)O4; x=0, 0.1, 0.3 and 0.5). The X-ray diffraction (XRD) measurements confirmed the presence of pure cubic spinel phase in all samples, while the transmission electron microscopy (TEM) showed sphere-like nanoparticles with a mean diameter of 6±1 nm. The amount of adsorbed oleic acid on the surface of the nanoparticles, determined by thermogravimetric (TG) analysis indicates the formation of a complete monolayer of surfactant. The FT-IR analysis substantiated the presence of oleic acid on the surface of the nanoparticles and discovered its covalent bonding to the metal atoms. Substitution of host-atoms was also confirmed by Raman spectroscopy. Magnetic measurements revealed the influence of heteroatoms on saturation magnetization and magnetic anisotropy, showing for all the samples superparamagnetic behaviour at room temperature. The substitution of Co2+ and Fe3+ ions with Zn2+ and Ga3+, respectively, leads to the change in chemical composition and cationic distribution of CFO and consequently to variation of its magnetic properties.
PB  - Belgrade : Materials Research Society of Serbia – MRS-Serbia
C3  - YUCOMAT 2021 : Twenty-second Annual Conference YUCOMAT 2021 : Programme and the Book of abstracts
T1  - The influence of heteroatoms on physicochemical properties of cobalt ferrite nanoparticles
SP  - 107
EP  - 107
UR  - https://hdl.handle.net/21.15107/rcub_vinar_12532
ER  - 

@conference{
author = "Jovanović, Sonja and Vukomanović, Marija and Spreitzer, Matjaž and Jovanović, Zoran and Maček- Kržmanc, Marjeta and Grujičić, Marija and Peddis, Davide",
year = "2021",
abstract = "In the last two decades, cobalt ferrite (CoFe2O4, CFO) has attracted extensive attention due to its applicability in data storage, catalysis, energy, environment, and in particular, biomedicine. To further extend applicability and improve understanding of fundamental processes, the present work investigates the influence of heteroatoms on physicochemical properties of CFO. Solvothermal method was used for designing a non-agglomerated particles with uniform morpho-structural properties. The physicochemical properties of Zn2+ and Ga3+ substituted CFO nanoparticles were examined (Co(1-x)ZnxFe2O4 and CoGaxFe(2-x)O4; x=0, 0.1, 0.3 and 0.5). The X-ray diffraction (XRD) measurements confirmed the presence of pure cubic spinel phase in all samples, while the transmission electron microscopy (TEM) showed sphere-like nanoparticles with a mean diameter of 6±1 nm. The amount of adsorbed oleic acid on the surface of the nanoparticles, determined by thermogravimetric (TG) analysis indicates the formation of a complete monolayer of surfactant. The FT-IR analysis substantiated the presence of oleic acid on the surface of the nanoparticles and discovered its covalent bonding to the metal atoms. Substitution of host-atoms was also confirmed by Raman spectroscopy. Magnetic measurements revealed the influence of heteroatoms on saturation magnetization and magnetic anisotropy, showing for all the samples superparamagnetic behaviour at room temperature. The substitution of Co2+ and Fe3+ ions with Zn2+ and Ga3+, respectively, leads to the change in chemical composition and cationic distribution of CFO and consequently to variation of its magnetic properties.",
publisher = "Belgrade : Materials Research Society of Serbia – MRS-Serbia",
journal = "YUCOMAT 2021 : Twenty-second Annual Conference YUCOMAT 2021 : Programme and the Book of abstracts",
title = "The influence of heteroatoms on physicochemical properties of cobalt ferrite nanoparticles",
pages = "107-107",
url = "https://hdl.handle.net/21.15107/rcub_vinar_12532"
}

Jovanović, S., Vukomanović, M., Spreitzer, M., Jovanović, Z., Maček- Kržmanc, M., Grujičić, M.,& Peddis, D.. (2021). The influence of heteroatoms on physicochemical properties of cobalt ferrite nanoparticles. in YUCOMAT 2021 : Twenty-second Annual Conference YUCOMAT 2021 : Programme and the Book of abstracts
Belgrade : Materials Research Society of Serbia – MRS-Serbia., 107-107.
https://hdl.handle.net/21.15107/rcub_vinar_12532

Jovanović S, Vukomanović M, Spreitzer M, Jovanović Z, Maček- Kržmanc M, Grujičić M, Peddis D. The influence of heteroatoms on physicochemical properties of cobalt ferrite nanoparticles. in YUCOMAT 2021 : Twenty-second Annual Conference YUCOMAT 2021 : Programme and the Book of abstracts. 2021;:107-107.
https://hdl.handle.net/21.15107/rcub_vinar_12532 .

Jovanović, Sonja, Vukomanović, Marija, Spreitzer, Matjaž, Jovanović, Zoran, Maček- Kržmanc, Marjeta, Grujičić, Marija, Peddis, Davide, "The influence of heteroatoms on physicochemical properties of cobalt ferrite nanoparticles" in YUCOMAT 2021 : Twenty-second Annual Conference YUCOMAT 2021 : Programme and the Book of abstracts (2021):107-107,
https://hdl.handle.net/21.15107/rcub_vinar_12532 .