Improved ceramic and electrical properties of CaZrO3-based proton-conducting materials prepared by a new convenient combustion synthesis method

Abstract

The present work emphasizes the features of a new combustion synthesis method suitable for easy synthesis and sintering of CaZrO3-based materials as promising proton-conducting electrolytes for electrochemical applications in solid oxide electrochemical devices. Sc- and In-doped CaZrO3 compounds are selected to be the objects of investigation and their crystal structure properties as well as microstructural, thermal and electrical characteristics are studied by the means of X-ray diffraction analysis, high-temperature dilatometry, scanning electron spectroscopy, impedance and 4-probe DC conductivity techniques. The established properties are critically compared with previously obtained data to confirm the prospects of the proposed method synthesis for the preparation of Zr-based proton-conducting ceramic materials. It is found that CaZr0.95Sc0.05O3–δ exhibits predominantly protonic conductivity under wet air atmospheres below 700°C; while, CaZr0.9In0.1O3–δ demonstrates a certain value of electronic conductivity along with ionic one.