Structure and synthesis optimisation of BSCFW, a self-assembled dynamic perovskite composite cathode for intermediate temperature SOFCs

The performance of new state-of-the-art Ba0.5Sr0.5(Co0.7Fe0.3)0.6875W0.3125O3-d (BSCFW) cathode materials for solid oxide fuel cells, which are composites of single- (SP) and double- perovskite (DP) phases we published recently, is highly correlated to the preparation route and processing conditions. This is mediated by the interplay between the separate phases through lattice mismatch and ability for the exchange of W6+ from DP to SP at operating conditions, significantly enhancing material stability. Using high-resolution neutron diffraction, we aim to understand the subtle structural differences induced through different preparative conditions in these materials. This knowledge will inform future processing routes to such materials as part of our current collaboration with industry for industrial-scale testing.

我们近期发表的最新一代高性能固体氧化物燃料电池（solid oxide fuel cell, SOFC）阴极材料Ba₀.₅Sr₀.₅(Co₀.₇Fe₀.₃)₀.₆₈₇₅W₀.₃₁₂₅O₃₋δ（BSCFW），为由单相钙钛矿（single-perovskite，SP）与双钙钛矿（double-perovskite，DP）相构成的复合材料。该材料的性能与制备路径及工艺条件密切相关，这种相关性通过两相之间的相互作用得以调控：晶格失配效应，以及运行条件下W⁶⁺从双钙钛矿相向单相钙钛矿相转移的能力，共同显著提升了材料的结构稳定性。本研究采用高分辨中子衍射技术，旨在阐明不同制备工艺对该类材料所诱导的细微结构差异。上述研究成果将为这类材料的后续工艺优化提供指导，这也是我们目前与工业界合作开展工业级测试项目的一部分。