TY  - JOUR
AU  - Jugović, Dragana
AU  - Mitrić, Miodrag
AU  - Milović, Miloš
AU  - Cvjetićanin, Nikola
AU  - Jokić, Bojan
AU  - Umićević, Ana
AU  - Uskoković, Dragan
PY  - 2017
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5856
AB  - Low intrinsic electronic conductivity is the main disadvantage of LiFePO4 when used as a cathode material in lithium ion batteries. The paper offers experimental proofs of the theoretical prediction that fluorine doping of LiFePO4 can enhance its electrical conductivity. The LiFePO4 and fluorine-doped LiFePO4 olivine type, carbon-free powders are synthesized and examined. The crystal structure refinements in the Pnma space group reveal that doping with fluorine ions preserves the olivine structure, while reducing both the lattice parameters and the antisite defect, and increasing the crystallite size. A small amount of incorporated fluorine enhances the electrical conductivity from 4.6×10−7 S cm−1 to 2.3×10−6 S cm−1 and has a positive impact on the electrochemical performance. Several spectroscopy techniques (Mössbauer, FTIR, and Raman) reveal differences between the two powders and additionally support the findings of both the Rietveld refinement and the conductivity measurements.
PB  - Elsevier
T2  - Ceramics International
T1  - The influence of fluorine doping on the structural and electrical properties of the LiFePO4 powder
EP  - 3230
IS  - 3
SP  - 3224
VL  - 43
DO  - 10.1016/j.ceramint.2016.11.149
UR  - https://hdl.handle.net/21.15107/rcub_dais_2352
ER  - 

@article{
author = "Jugović, Dragana and Mitrić, Miodrag and Milović, Miloš and Cvjetićanin, Nikola and Jokić, Bojan and Umićević, Ana and Uskoković, Dragan",
year = "2017",
abstract = "Low intrinsic electronic conductivity is the main disadvantage of LiFePO4 when used as a cathode material in lithium ion batteries. The paper offers experimental proofs of the theoretical prediction that fluorine doping of LiFePO4 can enhance its electrical conductivity. The LiFePO4 and fluorine-doped LiFePO4 olivine type, carbon-free powders are synthesized and examined. The crystal structure refinements in the Pnma space group reveal that doping with fluorine ions preserves the olivine structure, while reducing both the lattice parameters and the antisite defect, and increasing the crystallite size. A small amount of incorporated fluorine enhances the electrical conductivity from 4.6×10−7 S cm−1 to 2.3×10−6 S cm−1 and has a positive impact on the electrochemical performance. Several spectroscopy techniques (Mössbauer, FTIR, and Raman) reveal differences between the two powders and additionally support the findings of both the Rietveld refinement and the conductivity measurements.",
publisher = "Elsevier",
journal = "Ceramics International",
title = "The influence of fluorine doping on the structural and electrical properties of the LiFePO4 powder",
pages = "3230-3224",
number = "3",
volume = "43",
doi = "10.1016/j.ceramint.2016.11.149",
url = "https://hdl.handle.net/21.15107/rcub_dais_2352"
}

Jugović, D., Mitrić, M., Milović, M., Cvjetićanin, N., Jokić, B., Umićević, A.,& Uskoković, D.. (2017). The influence of fluorine doping on the structural and electrical properties of the LiFePO4 powder. in Ceramics International
Elsevier., 43(3), 3224-3230.
https://doi.org/10.1016/j.ceramint.2016.11.149
https://hdl.handle.net/21.15107/rcub_dais_2352

Jugović D, Mitrić M, Milović M, Cvjetićanin N, Jokić B, Umićević A, Uskoković D. The influence of fluorine doping on the structural and electrical properties of the LiFePO4 powder. in Ceramics International. 2017;43(3):3224-3230.
doi:10.1016/j.ceramint.2016.11.149
https://hdl.handle.net/21.15107/rcub_dais_2352 .

Jugović, Dragana, Mitrić, Miodrag, Milović, Miloš, Cvjetićanin, Nikola, Jokić, Bojan, Umićević, Ana, Uskoković, Dragan, "The influence of fluorine doping on the structural and electrical properties of the LiFePO4 powder" in Ceramics International, 43, no. 3 (2017):3224-3230,
https://doi.org/10.1016/j.ceramint.2016.11.149 .,
https://hdl.handle.net/21.15107/rcub_dais_2352 .

TY  - JOUR
AU  - Jugović, Dragana
AU  - Milović, Miloš
AU  - Ivanovski, Valentin N.
AU  - Avdeev, Maxim
AU  - Dominko, Robert
AU  - Jokić, Bojan
AU  - Uskoković, Dragan
PY  - 2014
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5786
AB  - A composite powder Li2FeSiO4/C is synthesized through a solid state reaction at 750 °C. The Rietveld crystal structure refinement is done in the monoclinic P21/n space group. It is found that the crystal structure is prone to “antisite” defect where small part of iron ion occupies exclusively Li(2) crystallographic position, of two different lithium tetrahedral positions (Li(1) and Li(2)). This finding is also confirmed by Mössbauer spectroscopy study: the sextet evidenced in the Mössbauer spectrum is assigned to the iron ions positioned at the Li(2) sites. A bond-valence energy landscape calculation is used to predict the conduction pathways of lithium ions. The calculations suggest that Li conductivity is two-dimensional in the (101) plane. Upon galvanostatic cyclings the structure starts to rearrange to inverse βII polymorph.
PB  - Elsevier B.V.
T2  - Journal of Power Sources
T1  - Structural study of monoclinic Li2FeSiO4 by X-ray diffraction and Mössbauer spectroscopy
EP  - 80
SP  - 75
VL  - 265
DO  - 10.1016/j.jpowsour.2014.04.121
UR  - https://hdl.handle.net/21.15107/rcub_dais_755
ER  - 

@article{
author = "Jugović, Dragana and Milović, Miloš and Ivanovski, Valentin N. and Avdeev, Maxim and Dominko, Robert and Jokić, Bojan and Uskoković, Dragan",
year = "2014",
abstract = "A composite powder Li2FeSiO4/C is synthesized through a solid state reaction at 750 °C. The Rietveld crystal structure refinement is done in the monoclinic P21/n space group. It is found that the crystal structure is prone to “antisite” defect where small part of iron ion occupies exclusively Li(2) crystallographic position, of two different lithium tetrahedral positions (Li(1) and Li(2)). This finding is also confirmed by Mössbauer spectroscopy study: the sextet evidenced in the Mössbauer spectrum is assigned to the iron ions positioned at the Li(2) sites. A bond-valence energy landscape calculation is used to predict the conduction pathways of lithium ions. The calculations suggest that Li conductivity is two-dimensional in the (101) plane. Upon galvanostatic cyclings the structure starts to rearrange to inverse βII polymorph.",
publisher = "Elsevier B.V.",
journal = "Journal of Power Sources",
title = "Structural study of monoclinic Li2FeSiO4 by X-ray diffraction and Mössbauer spectroscopy",
pages = "80-75",
volume = "265",
doi = "10.1016/j.jpowsour.2014.04.121",
url = "https://hdl.handle.net/21.15107/rcub_dais_755"
}

Jugović, D., Milović, M., Ivanovski, V. N., Avdeev, M., Dominko, R., Jokić, B.,& Uskoković, D.. (2014). Structural study of monoclinic Li2FeSiO4 by X-ray diffraction and Mössbauer spectroscopy. in Journal of Power Sources
Elsevier B.V.., 265, 75-80.
https://doi.org/10.1016/j.jpowsour.2014.04.121
https://hdl.handle.net/21.15107/rcub_dais_755

Jugović D, Milović M, Ivanovski VN, Avdeev M, Dominko R, Jokić B, Uskoković D. Structural study of monoclinic Li2FeSiO4 by X-ray diffraction and Mössbauer spectroscopy. in Journal of Power Sources. 2014;265:75-80.
doi:10.1016/j.jpowsour.2014.04.121
https://hdl.handle.net/21.15107/rcub_dais_755 .

Jugović, Dragana, Milović, Miloš, Ivanovski, Valentin N., Avdeev, Maxim, Dominko, Robert, Jokić, Bojan, Uskoković, Dragan, "Structural study of monoclinic Li2FeSiO4 by X-ray diffraction and Mössbauer spectroscopy" in Journal of Power Sources, 265 (2014):75-80,
https://doi.org/10.1016/j.jpowsour.2014.04.121 .,
https://hdl.handle.net/21.15107/rcub_dais_755 .

TY  - JOUR
AU  - Jugović, Dragana
AU  - Milović, Miloš
AU  - Ivanovski, Valentin N.
AU  - Avdeev, Maxim
AU  - Dominko, Robert
AU  - Jokić, Bojan
AU  - Uskoković, Dragan
PY  - 2014
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5787
AB  - A composite powder Li2FeSiO4/C is synthesized through a solid state reaction at 750 °C. The Rietveld crystal structure refinement is done in the monoclinic P21/n space group. It is found that the crystal structure is prone to “antisite” defect where small part of iron ion occupies exclusively Li(2) crystallographic position, of two different lithium tetrahedral positions (Li(1) and Li(2)). This finding is also confirmed by Mössbauer spectroscopy study: the sextet evidenced in the Mössbauer spectrum is assigned to the iron ions positioned at the Li(2) sites. A bond-valence energy landscape calculation is used to predict the conduction pathways of lithium ions. The calculations suggest that Li conductivity is two-dimensional in the (101) plane. Upon galvanostatic cyclings the structure starts to rearrange to inverse βII polymorph.
PB  - Elsevier B.V.
T2  - Journal of Power Sources
T1  - Structural study of monoclinic Li2FeSiO4 by X-ray diffraction and Mössbauer spectroscopy
EP  - 80
SP  - 75
VL  - 265
DO  - 10.1016/j.jpowsour.2014.04.121
UR  - https://hdl.handle.net/21.15107/rcub_dais_542
ER  - 

@article{
author = "Jugović, Dragana and Milović, Miloš and Ivanovski, Valentin N. and Avdeev, Maxim and Dominko, Robert and Jokić, Bojan and Uskoković, Dragan",
year = "2014",
abstract = "A composite powder Li2FeSiO4/C is synthesized through a solid state reaction at 750 °C. The Rietveld crystal structure refinement is done in the monoclinic P21/n space group. It is found that the crystal structure is prone to “antisite” defect where small part of iron ion occupies exclusively Li(2) crystallographic position, of two different lithium tetrahedral positions (Li(1) and Li(2)). This finding is also confirmed by Mössbauer spectroscopy study: the sextet evidenced in the Mössbauer spectrum is assigned to the iron ions positioned at the Li(2) sites. A bond-valence energy landscape calculation is used to predict the conduction pathways of lithium ions. The calculations suggest that Li conductivity is two-dimensional in the (101) plane. Upon galvanostatic cyclings the structure starts to rearrange to inverse βII polymorph.",
publisher = "Elsevier B.V.",
journal = "Journal of Power Sources",
title = "Structural study of monoclinic Li2FeSiO4 by X-ray diffraction and Mössbauer spectroscopy",
pages = "80-75",
volume = "265",
doi = "10.1016/j.jpowsour.2014.04.121",
url = "https://hdl.handle.net/21.15107/rcub_dais_542"
}

Jugović, D., Milović, M., Ivanovski, V. N., Avdeev, M., Dominko, R., Jokić, B.,& Uskoković, D.. (2014). Structural study of monoclinic Li2FeSiO4 by X-ray diffraction and Mössbauer spectroscopy. in Journal of Power Sources
Elsevier B.V.., 265, 75-80.
https://doi.org/10.1016/j.jpowsour.2014.04.121
https://hdl.handle.net/21.15107/rcub_dais_542

Jugović D, Milović M, Ivanovski VN, Avdeev M, Dominko R, Jokić B, Uskoković D. Structural study of monoclinic Li2FeSiO4 by X-ray diffraction and Mössbauer spectroscopy. in Journal of Power Sources. 2014;265:75-80.
doi:10.1016/j.jpowsour.2014.04.121
https://hdl.handle.net/21.15107/rcub_dais_542 .

Jugović, Dragana, Milović, Miloš, Ivanovski, Valentin N., Avdeev, Maxim, Dominko, Robert, Jokić, Bojan, Uskoković, Dragan, "Structural study of monoclinic Li2FeSiO4 by X-ray diffraction and Mössbauer spectroscopy" in Journal of Power Sources, 265 (2014):75-80,
https://doi.org/10.1016/j.jpowsour.2014.04.121 .,
https://hdl.handle.net/21.15107/rcub_dais_542 .

TY  - JOUR
AU  - Jugović, Dragana
AU  - Mitrić, Miodrag
AU  - Milović, Miloš
AU  - Jokić, Bojan M.
AU  - Vukomanovic, Marija
AU  - Suvorov, Danilo
AU  - Uskoković, Dragan
PY  - 2013
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5712
AB  - In this study, nanocrystalline LiFePO4/C composite powder has been synthesized via a cellulose matrix-assisted method. In an experiment conducted under extreme conditions involving rapid heating, short high-temperature delay, and subsequent quenching, well-ordered 35-nm crystallites have been obtained within 5 min. A quantitative filter paper has served both as a template and carbon source. It degrades pyrolytically through fragmentation reactions and formation of volatiles when exposed to rapid heating, which further has an impact on powder morphology, as revealed by electron microscopy studies. The electrochemical measurements in terms of galvanostatic cycling have shown that the approach presented in this study may enable to reach good rate capability and excellent cycling stability. (C) 2013 Elsevier B.V. All rights reserved.
T2  - Powder Technology
T1  - Properties of quenched LiFePO4/C powder obtained via cellulose matrix-assisted method
EP  - 544
SP  - 539
VL  - 246
DO  - 10.1016/j.powtec.2013.06.021
ER  - 

@article{
author = "Jugović, Dragana and Mitrić, Miodrag and Milović, Miloš and Jokić, Bojan M. and Vukomanovic, Marija and Suvorov, Danilo and Uskoković, Dragan",
year = "2013",
abstract = "In this study, nanocrystalline LiFePO4/C composite powder has been synthesized via a cellulose matrix-assisted method. In an experiment conducted under extreme conditions involving rapid heating, short high-temperature delay, and subsequent quenching, well-ordered 35-nm crystallites have been obtained within 5 min. A quantitative filter paper has served both as a template and carbon source. It degrades pyrolytically through fragmentation reactions and formation of volatiles when exposed to rapid heating, which further has an impact on powder morphology, as revealed by electron microscopy studies. The electrochemical measurements in terms of galvanostatic cycling have shown that the approach presented in this study may enable to reach good rate capability and excellent cycling stability. (C) 2013 Elsevier B.V. All rights reserved.",
journal = "Powder Technology",
title = "Properties of quenched LiFePO4/C powder obtained via cellulose matrix-assisted method",
pages = "544-539",
volume = "246",
doi = "10.1016/j.powtec.2013.06.021"
}

Jugović, D., Mitrić, M., Milović, M., Jokić, B. M., Vukomanovic, M., Suvorov, D.,& Uskoković, D.. (2013). Properties of quenched LiFePO4/C powder obtained via cellulose matrix-assisted method. in Powder Technology, 246, 539-544.
https://doi.org/10.1016/j.powtec.2013.06.021

Jugović D, Mitrić M, Milović M, Jokić BM, Vukomanovic M, Suvorov D, Uskoković D. Properties of quenched LiFePO4/C powder obtained via cellulose matrix-assisted method. in Powder Technology. 2013;246:539-544.
doi:10.1016/j.powtec.2013.06.021 .

Jugović, Dragana, Mitrić, Miodrag, Milović, Miloš, Jokić, Bojan M., Vukomanovic, Marija, Suvorov, Danilo, Uskoković, Dragan, "Properties of quenched LiFePO4/C powder obtained via cellulose matrix-assisted method" in Powder Technology, 246 (2013):539-544,
https://doi.org/10.1016/j.powtec.2013.06.021 . .