Enhancing the sinterability and electrical properties of BaZr <sub>0.1</sub> Ce <sub>0.7</sub> Y <sub>0.2</sub> O <sub>3‐δ</sub> proton‐conducting ceramic electrolyte
Shenglong Yu, Zhen Wang, Lei Yang, Jincheng Liu, Rui Guan, Youcheng Xiao, Tianmin He
Abstract
Abstract A novel strategy was proposed to enhance the sinterability and electrical properties of BaZr 0.1 Ce 0.7 Y 0.2 O 3‐δ (BZCY) proton‐conducting electrolyte by adding 10 wt.% La 0.9 Sr 0.1 Ga 0.8 Mg 0.2 O 3‐δ (LSGM) to form a 90 wt.% BZCY–10 wt.% LSGM (BL91) composite electrolyte. XRD patterns showed that no reaction occurred between the BZCY and LSGM electrolytes after sintering at 1400°C, 1450°C, 1500°C, and 1550°C for 10 h. The BL91 composite electrolyte exhibited higher relative densities and Vickers hardness and excellent electrical properties compared with those of the BZCY electrolyte. A combined approach of equivalent circuit model and distribution of relaxation time analysis was used to distinguish the bulk and grain‐boundary contributions to the total conductivity and electrode processes. The introduction of 10 wt.% LSGM serves as a grain‐boundary pinning phase, which can reduce the mobility of grain boundaries, thereby increasing sintered density and enhancing conductivity in BL91. A solid oxide fuel cell with proton‐conducting BL91 and BZCY membranes was tested, in which the former displayed higher power outputs than the latter. Ohmic and interfacial polarization resistances decreased by approximately 20%, thereby revealing the remarkable electrical properties of the BL91 electrolyte. Results demonstrated that BL91 composite is a development prospect proton‐conducting electrolyte.