najoNanosystems: Physics, Chemistry, MathematicsНаносистемы: физика, химия, математика2220-80542305-7971Университет ИТМО10.17586/2220-8054-2024-15-1-65-79najo-65Research ArticleCHEMISTRY AND MATERIAL SCIENCEХИМИЯ И МАТЕРИАЛОВЕДЕНИЕEquilibrium of intrinsic and impurity point defects in Ca-doped Sm2Zr2O7Равновесие собственных и примесных точечных дефектов в кальций-допированном Sm2Zr2O7https://orcid.org/0000-0002-0247-6198ВоротниковВ. А.VorotnikovV. A.

Vladimir A. Vorotnikov

Kirov, 610000; Novosibirsk, 630090

vorotnikov130@mail.ruhttps://orcid.org/0000-0001-9237-8307БеляковС. А.BelyakovS. A.

Semyon A. Belyakov

Yekaterinburg 620137

bca2@mail.ruhttps://orcid.org/0000-0002-7666-831XИвановА. В.IvanovA. V.

Alexey V. Ivanov

Kirov 610000; Novosibirsk, 630090

alehaww@gmail.comhttps://orcid.org/0000-0002-0369-3274НовиковаЮ. В.NovikovaYu. V.

Yulia V. Novikova

Yekaterinburg 620137

meryl18@mail.ruhttps://orcid.org/0000-0002-6772-3321СтроеваА. Ю.StroevaA. Yu.

Anna Yu. Stroeva

Kirov 610000

stroevaanna@yandex.ruhttps://orcid.org/0000-0002-5484-4642ГребеневВ. В.GrebenevV. V.

Vadim V. Grebenev

Moscow 119333

vadimgrebenev@mail.ruhttps://orcid.org/0000-0003-0894-5087ХмеленинД. Н.KhmeleninD. N.

Dmitry N. Khmelenin

Moscow 119333

xorrunn@gmail.comhttps://orcid.org/0000-0003-3951-8985ЕмельяноваО. В.EmelyanovaO. V.

Olga V. Emelyanova

Moscow 119333

eolga@bk.ruhttps://orcid.org/0000-0002-2701-4619ПлехановМ. С.PlekhanovM. S.

Maksim S. Plekhanov

Aachen 52066

plexanovmax@mail.ruhttps://orcid.org/0000-0002-0700-662XКузьминА. В.KuzminA. V.

Anton V. Kuzmin

Kirov 610000; Novosibirsk, 630090

a.v.kuzmin@yandex.ruInstitute of Chemistry and Ecology, Vyatka State University; Institute of Solid-State Chemistry and Mechanochemistry SB RASRussian FederationInstitute of High-Temperature Electrochemistry UB RASRussian FederationInstitute of Chemistry and Ecology, Vyatka State UniversityRussian FederationShubnikov Institute of Crystallography of Federal Scientific Research Centre “Crystallography and Photonics” of the RASRussian FederationInstitute of Crystallography, RWTH Aachen UniversityGermany2024310520251516579Copyright © Vorotnikov V.A., Belyakov S.A., Ivanov A.V., Novikova Y.V., Stroeva A.Y., Grebenev V.V., Khmelenin D.N., Emelyanova O.V., Plekhanov M.S., Kuzmin A.V., 20252025Воротников В.А., Беляков С.А., Иванов А.В., Новикова Ю.В., Строева А.Ю., Гребенев В.В., Хмеленин Д.Н., Емельянова О.В., Плеханов М.С., Кузьмин А.В.Vorotnikov V.A., Belyakov S.A., Ivanov A.V., Novikova Y.V., Stroeva A.Y., Grebenev V.V., Khmelenin D.N., Emelyanova O.V., Plekhanov M.S., Kuzmin A.V.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://nanojournal.ifmo.ru/jour/article/view/65

In this work, a doping strategy was used to achieve a good conductivity in samarium zirconate which crystallizes in the pyrochlore. The production of nanopowders made it possible to form high-density ceramics with an optimal microstructure. It is shown that intrinsic and impurity defects coexist in Sm2−xCaxZr2O7−δ, impairing ion transport at high doping levels. Despite this, Sm1.95Ca0.05Zr2O7−δ maintains low activation energy of the parent and has good ionic conductivity (10−3 S·cm−1 at 600 ◦C) which is one of the largest among oxide pyrochlores. It has been shown to have a good chemical stability. The material has a thermal expansion coefficient (TEC) of 12 ppm K−1 which is higher than YSZ and provides better compatibility with electrode materials. The above makes it possible to successfully use it as a highly stable oxygen electrolyte or an intermediate thin layer at the electrolyte-electrode interface in electrochemical devices.

В данной работе для достижения хорошей проводимости цирконата самария со структурой пирохлора использован подход допирования. Полученные наноразмерные порошки были спечены в высокоплотную керамику. Показано, что в Sm2-xCaxZr2O7−δ присутствуют как собственные, так и примесные дефекты, блокируя перенос ионов при высоких степенях добавки. Несмотря на это, Sm1.95Ca0.05Zr2O7−δ сохраняет низкую энергию активации как у недопированного материала и обладает хорошей ионной проводимостью (10-3 S cm-1 at 600 °C), которая является одной из самых высоких среди пирохлоров. Было доказано, что данный состав обладает хорошей химической стабильностью. Материал имеет коэффициент теплового расширения около 12∙10-6 K-1, который выше, чем у YSZ, что обеспечивает лучшую совместимость с электродными материалами. Все вышесказанное позволяет рекомендовать данный состав в качестве высокостабильного кислородного электролита или промежуточного тонкого слоя на границе раздела электролит-электрод в электрохимических устройствах.

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The authors declare that there are no conflicts of interest present.