Perovskite oxide exsolution process and structure regulation strategy: a review

Traditional surface modification methods such as physical or chemical vapor deposition and impregnation have been widely used to modify perovskite surfaces. However, there is weak interaction between metal nanoparticles (NPs) loaded via these methods and the perovskite oxide support, which may lead to issues such as deactivation during application owing to poor stability, easy agglomeration, and carbon deposition. Exsolution refers to the in-situ growth of NPs on the surface of parent oxides. The presence of NPs increases the number of active sites for the reaction, and NPs exhibit strong interaction with the matrix, showing excellent catalytic performance and high stability. Therefore, in recent years, the field of in-situ exsolution has received extensive attention. Based on this, this paper starts from exsolution phenomena of perovskite oxides, reviews existing exsolution methods, sorts out structurally regulated exsolution strategies of perovskite oxides in terms of A-site defects, B-site cation dopants, and phase transformation, introduces application fields of the in-situ exsolution, and provides prospect.