Synthesis and properties of core–shell structured BaCe0.9Y0.1O2.95:BaZr0.9Y0.1O2.95

The perovskite proton conductor BaZr0.9Y0.1O2.95 (BZY10) shows better chemical stability but lower conductivity than BaCe0.9Y0.1O2.95 (BCY10). In this paper we attempted to synthesize BCY10:BZY10 core–shell materials in which BCY10 particles prepared by solid reaction were wrapped by a sol–gel deposited thin layer of BZY10 with ZnO as sintering aid to improve the sinterability of the materials. The effects of the BCY10/BZY10 ratios on the phase purity, microstructure, chemical stability and electrical conductivity of the samples were characterized by XRD, TEM, SEM, TGA and electrochemical impedance spectroscopy. A dense core–shell structure was formed after being sintered at 1300 °C for 10 h. The core–shell samples displayed improved stability against CO2 and water vapor at high temperature. With BCY10/BZY10 ratio varying from 9:1 to 7:3, the core–shell samples became more stable, and the total conductivities decreased.