TY  - CONF
AU  - Dapčević, Aleksandra
AU  - Dejan, Poleti
AU  - Radojković, Aleksandar
AU  - Branković, Goran
PY  - 2017
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/2756
PB  - Institut Ruđer Bošković, Zagreb, Hrvatska
C3  - 1st Solid-State Science & Research Meeting
T1  - Ionic conductivity and stability: Tm3+- vs. Lu3+-doped δ-Bi2O3
EP  - 43
SP  - 42
UR  - https://hdl.handle.net/21.15107/rcub_rimsi_2756
ER  - 

@conference{
author = "Dapčević, Aleksandra and Dejan, Poleti and Radojković, Aleksandar and Branković, Goran",
year = "2017",
publisher = "Institut Ruđer Bošković, Zagreb, Hrvatska",
journal = "1st Solid-State Science & Research Meeting",
title = "Ionic conductivity and stability: Tm3+- vs. Lu3+-doped δ-Bi2O3",
pages = "43-42",
url = "https://hdl.handle.net/21.15107/rcub_rimsi_2756"
}

Dapčević, A., Dejan, P., Radojković, A.,& Branković, G.. (2017). Ionic conductivity and stability: Tm3+- vs. Lu3+-doped δ-Bi2O3. in 1st Solid-State Science & Research Meeting
Institut Ruđer Bošković, Zagreb, Hrvatska., 42-43.
https://hdl.handle.net/21.15107/rcub_rimsi_2756

Dapčević A, Dejan P, Radojković A, Branković G. Ionic conductivity and stability: Tm3+- vs. Lu3+-doped δ-Bi2O3. in 1st Solid-State Science & Research Meeting. 2017;:42-43.
https://hdl.handle.net/21.15107/rcub_rimsi_2756 .

Dapčević, Aleksandra, Dejan, Poleti, Radojković, Aleksandar, Branković, Goran, "Ionic conductivity and stability: Tm3+- vs. Lu3+-doped δ-Bi2O3" in 1st Solid-State Science & Research Meeting (2017):42-43,
https://hdl.handle.net/21.15107/rcub_rimsi_2756 .

TY  - CONF
AU  - Dapčević, Aleksandra
AU  - Dejan, Poleti
AU  - Radojković, Aleksandar
AU  - Branković, Goran
PY  - 2017
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/2868
AB  - Due to the increasing demands for new highly efficient and environmentally
friendly energy conversion technologies, the oxide ion conductors applicable in
solid oxide fuel cells (SOFCs) have widely been investigated. The high temperatureδ-Bi2O3 phase has been proposed as a good candidate for electrolyte in SOFCs
because it is the fastest known ionic conductor.
In this study, the possibility to stabilize O
2–
ion conductors related to the -Bi2O3
polymorph in Bi12VxO18+5x/2 (x = 0.5–1) system was investigated. Six starting
mixtures of α-Bi2O3 and V2O5 were dry homogenized in an agate mortar, heat
treated at 1000 °C for 1 h and then slowly furnace cooled. The samples were
characterized by XRD, TEM/SAED, optical microscopy, DTA and EIS techniques.
Based on XRD and TEM/SAED, if x ≥ 0.6 the high-temperature reaction
between α-Bi2O3 and V2O5 resulted in formation of microcrystalline single-phase
specimens containing the phase based on δ-Bi2O3. The obtained phases showed
main diffraction peaks corresponding to the cubic -Bi2O3 (space group Fm-3m and
a ≈ 5.6 Å). However, the detected weak reflections indicate that the true unit cell is
the 3×3×3 supercell with a ≈ 16.6 Å. An expected decrease of the unit cell
parameters with the dopant amount was found as the consequence of smaller dopant
ionic radius {ri(V5+) = 0.54 Ǻ and ri(Bi3+) = 1.03 Ǻ in the six-coordinated
environment [1]}. In the case of Bi12V0.5O19.25, traces of α-Bi2O3 were also found.
The XRD data of Bi12V0.7O19.75 were used for the Rietveld refinement giving
Bi102V6O168 as the composition of the 3×3×3 supercell. The octahedrally coordinated
V
5+ ions fully occupy 4a Wyckoff position, i.e. the corners and face centers of cubic
supercell, and partially occupy 32f. The Bi3+ ions are placed at the rest of 32f and at
24e and 48h with full occupation. At the 32f site, the cations are surrounded by five
oxide ions making a square pyramid. At the 24e site, the Bi3+ ions with four oxide
ions form a square pyramid with the cation at the apex. The coordination of Bi3+ at
the 48h is square planar.
Cyclic DTA curves showed that the following 3×3×3 → -Bi2O3 → -Bi2O3 →
Bi2O3(l) consecutive phase transitions occur on heating. On cooling, -Bi2O3
crystallizes from the melts and remains stable to about 530 °C. At this temperature,
an order-disorder transition takes place, i.e. -Bi2O3 → 3×3×3.
The sintered disk-shaped pellets were characterized by EIS at temperatures
between 760 and 820 °C. The sample with x = 0.6 demonstrates one of the highest
known conductivity among the published O2–
ion conductors, i.e. 0.66 S cm–1
at 760
°C with the lowest activation energy of 0.21(1) eV.
1. R. D. Shannon, Acta Cryst. A 32 (1976) 751
PB  - Društvo za keramičke materijale Srbije
C3  - 4th Conference of the Serbian Ceramic Society
T1  - HIGHLY CONDUCTIVE V-DOPED d-Bi2O3 WITH 3×3×3 SUPERSTRUCTURE
EP  - 83
SP  - 82
UR  - https://hdl.handle.net/21.15107/rcub_rimsi_2868
ER  - 

@conference{
author = "Dapčević, Aleksandra and Dejan, Poleti and Radojković, Aleksandar and Branković, Goran",
year = "2017",
abstract = "Due to the increasing demands for new highly efficient and environmentally
friendly energy conversion technologies, the oxide ion conductors applicable in
solid oxide fuel cells (SOFCs) have widely been investigated. The high temperatureδ-Bi2O3 phase has been proposed as a good candidate for electrolyte in SOFCs
because it is the fastest known ionic conductor.
In this study, the possibility to stabilize O
2–
ion conductors related to the -Bi2O3
polymorph in Bi12VxO18+5x/2 (x = 0.5–1) system was investigated. Six starting
mixtures of α-Bi2O3 and V2O5 were dry homogenized in an agate mortar, heat
treated at 1000 °C for 1 h and then slowly furnace cooled. The samples were
characterized by XRD, TEM/SAED, optical microscopy, DTA and EIS techniques.
Based on XRD and TEM/SAED, if x ≥ 0.6 the high-temperature reaction
between α-Bi2O3 and V2O5 resulted in formation of microcrystalline single-phase
specimens containing the phase based on δ-Bi2O3. The obtained phases showed
main diffraction peaks corresponding to the cubic -Bi2O3 (space group Fm-3m and
a ≈ 5.6 Å). However, the detected weak reflections indicate that the true unit cell is
the 3×3×3 supercell with a ≈ 16.6 Å. An expected decrease of the unit cell
parameters with the dopant amount was found as the consequence of smaller dopant
ionic radius {ri(V5+) = 0.54 Ǻ and ri(Bi3+) = 1.03 Ǻ in the six-coordinated
environment [1]}. In the case of Bi12V0.5O19.25, traces of α-Bi2O3 were also found.
The XRD data of Bi12V0.7O19.75 were used for the Rietveld refinement giving
Bi102V6O168 as the composition of the 3×3×3 supercell. The octahedrally coordinated
V
5+ ions fully occupy 4a Wyckoff position, i.e. the corners and face centers of cubic
supercell, and partially occupy 32f. The Bi3+ ions are placed at the rest of 32f and at
24e and 48h with full occupation. At the 32f site, the cations are surrounded by five
oxide ions making a square pyramid. At the 24e site, the Bi3+ ions with four oxide
ions form a square pyramid with the cation at the apex. The coordination of Bi3+ at
the 48h is square planar.
Cyclic DTA curves showed that the following 3×3×3 → -Bi2O3 → -Bi2O3 →
Bi2O3(l) consecutive phase transitions occur on heating. On cooling, -Bi2O3
crystallizes from the melts and remains stable to about 530 °C. At this temperature,
an order-disorder transition takes place, i.e. -Bi2O3 → 3×3×3.
The sintered disk-shaped pellets were characterized by EIS at temperatures
between 760 and 820 °C. The sample with x = 0.6 demonstrates one of the highest
known conductivity among the published O2–
ion conductors, i.e. 0.66 S cm–1
at 760
°C with the lowest activation energy of 0.21(1) eV.
1. R. D. Shannon, Acta Cryst. A 32 (1976) 751",
publisher = "Društvo za keramičke materijale Srbije",
journal = "4th Conference of the Serbian Ceramic Society",
title = "HIGHLY CONDUCTIVE V-DOPED d-Bi2O3 WITH 3×3×3 SUPERSTRUCTURE",
pages = "83-82",
url = "https://hdl.handle.net/21.15107/rcub_rimsi_2868"
}

Dapčević, A., Dejan, P., Radojković, A.,& Branković, G.. (2017). HIGHLY CONDUCTIVE V-DOPED d-Bi2O3 WITH 3×3×3 SUPERSTRUCTURE. in 4th Conference of the Serbian Ceramic Society
Društvo za keramičke materijale Srbije., 82-83.
https://hdl.handle.net/21.15107/rcub_rimsi_2868

Dapčević A, Dejan P, Radojković A, Branković G. HIGHLY CONDUCTIVE V-DOPED d-Bi2O3 WITH 3×3×3 SUPERSTRUCTURE. in 4th Conference of the Serbian Ceramic Society. 2017;:82-83.
https://hdl.handle.net/21.15107/rcub_rimsi_2868 .

Dapčević, Aleksandra, Dejan, Poleti, Radojković, Aleksandar, Branković, Goran, "HIGHLY CONDUCTIVE V-DOPED d-Bi2O3 WITH 3×3×3 SUPERSTRUCTURE" in 4th Conference of the Serbian Ceramic Society (2017):82-83,
https://hdl.handle.net/21.15107/rcub_rimsi_2868 .

TY  - CONF
AU  - Zdravkovic, Jelena
AU  - Radovanovic, Lidija
AU  - Simović, Bojana
AU  - Dejan, Poleti
AU  - Rogan, Jelena
AU  - Radovanovic, Zeljko
AU  - Mihajlovski, Katarina
PY  - 2017
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/3080
AB  - Coordination chemistry provides the know-how for the synthesis of the
precursor compounds with variable composition and structures, while the thermal
induced changes may control the crystalline structure, phase composition,
morphology, size, texture, and other properties of their pyrolytic products [1]. In
terms of coordination chemistry and thermal analysis, our research has been focused
on the synthesis of mixed ligand complexes [2] that can be used as precursors for
obtaining diverse (compositional and structural) oxides, depending on their
thermoreactivity.
The main goal of this approach was the reduction of the temperature at which
the oxides are formed (up to 600–700 °C) comparative to the standard ceramic
methods. The effect of the different atmospheres (dynamic air or N2) on the thermal
decomposition of Zn benzenedicarboxylate complexes with 2,2’-dipyridylamine was
investigated. The formation of ZnO nanopowders was identified using XRPD and
FESEM techniques. The influence of the adopted architecture of ternary metal
complexes used as templates for ZnO nanopowders was discussed. The thermal
decomposition kinetics of precursors was studied under non-isothermal conditions.
In addition, the antibacterial activity of obtained ZnO nanopowders was also
analyzed. 
1. C.N.R. Rao, A. Müller, A.K. Cheetham, The Chemistry of Nanomaterials, Wiley
VCH Verlag GmbH & CoKGaA, 2003.
2. L. Radovanović, J. Rogan, D. Poleti, M. Milutinović, M.V. Rodić, Polyhedron, 112
(2016) 18
PB  - Institute for Multidisciplinary Research, University of Belgrade Kneza Višeslava 1, 11000 Belgrade, Serbia
C3  - 4th International Conference The Serbian Society for Ceramic Materials, Belgrade, Serbia
T1  - ZnO nanopowders obtained by thermolysis of zinc benzenedicarboxylate complexes with 2,2’-dipyridylamine
SP  - 79
UR  - https://hdl.handle.net/21.15107/rcub_rimsi_3080
ER  - 

@conference{
author = "Zdravkovic, Jelena and Radovanovic, Lidija and Simović, Bojana and Dejan, Poleti and Rogan, Jelena and Radovanovic, Zeljko and Mihajlovski, Katarina",
year = "2017",
abstract = "Coordination chemistry provides the know-how for the synthesis of the
precursor compounds with variable composition and structures, while the thermal
induced changes may control the crystalline structure, phase composition,
morphology, size, texture, and other properties of their pyrolytic products [1]. In
terms of coordination chemistry and thermal analysis, our research has been focused
on the synthesis of mixed ligand complexes [2] that can be used as precursors for
obtaining diverse (compositional and structural) oxides, depending on their
thermoreactivity.
The main goal of this approach was the reduction of the temperature at which
the oxides are formed (up to 600–700 °C) comparative to the standard ceramic
methods. The effect of the different atmospheres (dynamic air or N2) on the thermal
decomposition of Zn benzenedicarboxylate complexes with 2,2’-dipyridylamine was
investigated. The formation of ZnO nanopowders was identified using XRPD and
FESEM techniques. The influence of the adopted architecture of ternary metal
complexes used as templates for ZnO nanopowders was discussed. The thermal
decomposition kinetics of precursors was studied under non-isothermal conditions.
In addition, the antibacterial activity of obtained ZnO nanopowders was also
analyzed. 
1. C.N.R. Rao, A. Müller, A.K. Cheetham, The Chemistry of Nanomaterials, Wiley
VCH Verlag GmbH & CoKGaA, 2003.
2. L. Radovanović, J. Rogan, D. Poleti, M. Milutinović, M.V. Rodić, Polyhedron, 112
(2016) 18",
publisher = "Institute for Multidisciplinary Research, University of Belgrade Kneza Višeslava 1, 11000 Belgrade, Serbia",
journal = "4th International Conference The Serbian Society for Ceramic Materials, Belgrade, Serbia",
title = "ZnO nanopowders obtained by thermolysis of zinc benzenedicarboxylate complexes with 2,2’-dipyridylamine",
pages = "79",
url = "https://hdl.handle.net/21.15107/rcub_rimsi_3080"
}

Zdravkovic, J., Radovanovic, L., Simović, B., Dejan, P., Rogan, J., Radovanovic, Z.,& Mihajlovski, K.. (2017). ZnO nanopowders obtained by thermolysis of zinc benzenedicarboxylate complexes with 2,2’-dipyridylamine. in 4th International Conference The Serbian Society for Ceramic Materials, Belgrade, Serbia
Institute for Multidisciplinary Research, University of Belgrade Kneza Višeslava 1, 11000 Belgrade, Serbia., 79.
https://hdl.handle.net/21.15107/rcub_rimsi_3080

Zdravkovic J, Radovanovic L, Simović B, Dejan P, Rogan J, Radovanovic Z, Mihajlovski K. ZnO nanopowders obtained by thermolysis of zinc benzenedicarboxylate complexes with 2,2’-dipyridylamine. in 4th International Conference The Serbian Society for Ceramic Materials, Belgrade, Serbia. 2017;:79.
https://hdl.handle.net/21.15107/rcub_rimsi_3080 .

Zdravkovic, Jelena, Radovanovic, Lidija, Simović, Bojana, Dejan, Poleti, Rogan, Jelena, Radovanovic, Zeljko, Mihajlovski, Katarina, "ZnO nanopowders obtained by thermolysis of zinc benzenedicarboxylate complexes with 2,2’-dipyridylamine" in 4th International Conference The Serbian Society for Ceramic Materials, Belgrade, Serbia (2017):79,
https://hdl.handle.net/21.15107/rcub_rimsi_3080 .