Вид документа : Статья из журнала Шифр издания : 54/A 10 Автор(ы) : Istomin S. Ya., Antipov E. V., Svensson G., Attfield J. P., Kozhevnikov V. L., Leonidov I. A., Patrakeev M. V., Mitberg E. B. Заглавие : A Novel Complex Cobalt Gallium Oxide Ca2Co0.8Ga1.2O4.8: Synthesis and High-Temperature Electron Transport Properties Параллельн. заглавия :A Novel Complex Cobalt Gallium Oxide Ca2Co0.8Ga1.2O4.8: Synthesis and High-Temperature Electron Transport Properties Место публикации : Journal of Solid State Chemistry. - 2002. - V. 167, N 1. - С. 196-202. - ISSN 0022-4596. - ISSN 0022-4596 ББК : 54 Предметные рубрики: ХИМИЧЕСКИЕ НАУКИ Аннотация: A new complex oxide with the cation ratio Ca:Co:Ga = 2:0.8:1.2 has been synthesized in air at 1150oC. The cobalt atoms adopt oxidation states 2+ and 3+ in equal amounts giving an oxygen content corresponding to the composition Ca2Co0.8Ga1.2O4.8. It crystallizes in F-centered cubic structure with a = 15.0558 Angstrom. Conductivity measurements performed at high temperatures revealed that the temperature increase gives a charge disproportionation of Co3+ species resulting in a small concentration of Co4+ species and thus a small p-type conductivity in the oxide. A decrease of the oxygen pressure promotes oxygen depletion from the oxide and a deterioration of the conductivity. The electric properties are interpreted within a small polaron conduction mechanism. An unusually large mobility activation energy of 0.45 eV can be explained by a large spatial separation of cobalt cations in the structure Доп.точки доступа: Istomin, S. Ya.; Antipov, E. V.; Svensson, G.; Attfield, J. P.; Kozhevnikov, V. L.; Кожевников Виктор Леонидович; Leonidov, I. A.; Леонидов Илья Аркадьевич; Patrakeev, M. V.; Патракеев Михаил Валентинович; Mitberg, E. B.; Митберг Эдуард Борисович