TY - JOUR

T1 - Oxygen-Ion and Proton Transport of Origin and Ca-Doped La2ZnNdO5.5 Materials

AU - Belova, Ksenia

AU - Egorova, Anastasia

AU - Pachina, Svetlana

AU - Animitsa, Irina

AU - Medvedev, Dmitry

N1 - The research funding from the Ministry of Science and Higher Education of the Russian Federation (Ural Federal University Program of Development within the Priority-2030 Program) is gratefully acknowledged.

PY - 2023

Y1 - 2023

N2 - Oxygen-ionic and proton-conducting oxides are widely studied materials for their application in various electrochemical devices such as solid oxide fuel cells and electrolyzers. Rare earth oxides are known as a class of ionic conductors. In this paper, La2ZnNdO5.5 and its Ca-doped derivatives La2Nd0.9Ca0.1ZnO5.45 and La2ZnNd0.9Ca0.1O5.45 were obtained by a solid-state reaction route. Phase composition, lattice parameters, and hydration capability were investigated by X-ray diffraction and thermogravimetric analyses. The conductivities of these materials were measured by the electrochemical impedance spectroscopy technique in dry (pH2O = 3.5 × 10−5 atm) and wet (pH2O = 2 × 10−2 atm) air. All phases crystallized in a trigonal symmetry with P3m1 space group. The conductivity difference between undoped and calcium-doped samples is more than two orders of magnitude due to the appearance of oxygen vacancies during acceptor doping, which are responsible for a higher ionic conductivity. The La2Nd0.9Ca0.1ZnO5.45 sample shows the highest conductivity of about 10−3 S∙cm−1 at 650 °C. The Ca-doped phases are capable of reversible water uptake, confirming their proton-conducting nature.

AB - Oxygen-ionic and proton-conducting oxides are widely studied materials for their application in various electrochemical devices such as solid oxide fuel cells and electrolyzers. Rare earth oxides are known as a class of ionic conductors. In this paper, La2ZnNdO5.5 and its Ca-doped derivatives La2Nd0.9Ca0.1ZnO5.45 and La2ZnNd0.9Ca0.1O5.45 were obtained by a solid-state reaction route. Phase composition, lattice parameters, and hydration capability were investigated by X-ray diffraction and thermogravimetric analyses. The conductivities of these materials were measured by the electrochemical impedance spectroscopy technique in dry (pH2O = 3.5 × 10−5 atm) and wet (pH2O = 2 × 10−2 atm) air. All phases crystallized in a trigonal symmetry with P3m1 space group. The conductivity difference between undoped and calcium-doped samples is more than two orders of magnitude due to the appearance of oxygen vacancies during acceptor doping, which are responsible for a higher ionic conductivity. The La2Nd0.9Ca0.1ZnO5.45 sample shows the highest conductivity of about 10−3 S∙cm−1 at 650 °C. The Ca-doped phases are capable of reversible water uptake, confirming their proton-conducting nature.

UR - http://www.scopus.com/inward/record.url?partnerID=8YFLogxK&scp=85160248644

UR - https://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=tsmetrics&SrcApp=tsm_test&DestApp=WOS_CPL&DestLinkType=FullRecord&KeyUT=001033220300001

U2 - 10.3390/inorganics11050196

DO - 10.3390/inorganics11050196

M3 - Article

VL - 11

JO - Inorganics

JF - Inorganics

SN - 2304-6740

IS - 5

M1 - 196

ER -