Fabrication, microstructure, mechanical strength and oxygen permeation of Ba(Sr)Zr(CoFe)O_3-particles-dispersed Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3-delta) mixed-conducting composites

摘要

A mixed-conducting Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3-delta) (BSCF5582)-based composite was developed by addition of ZrO_2 and iso-molar excess BaO to introduce BaZrO_3-based secondary phase particles (SPP). It was revealed that as-synthesized composite could get well-distributed SPP and fine-grained microstructure due to the grain growth inhibition of the SPP. For the composite with addition of 10 mol percent ZrO_2 + 10 mol percent BaO, a well-developed and fine-grained microstructure has been obtained. Compared to the pure phase BSCF5582, the three-point bending strength of the composite with addition of 5 mol percent ZrO_2 + 5 mol percent BaO increases by 68 percent and its oxygen permeation rate is much higher below 830 deg C with the smaller apparent activation energy.