Exsolution: A promising strategy for constructing advanced composite solids

Abstract

The composite solids formed by combining two or more functional solids share enhanced performance and even novel functions, which has aroused enormous concern for developing highly efficient energy-related catalysts. Exsolution refers to the process that the second phase is separated from the lattice and then uniformly anchors on the surface of matrix oxides, which is a promising strategy for achieving excellent catalysts due to the good dispersion and stability of exsolved particles as well as the intense particle–matrix interaction. Recently, the growing number of published papers witnesses and reflects the significance and the trend in the development of exsolution-treated composite solid catalysts. Hence, a timely and detailed summary of the recent advances in exsolution is presented in this brief review. After specially clarifying the basic mechanism and promotion strategies of exsolution, we systematically introduce the recent progress in design, synthesis, and application of exsolution-treated composite solid catalysts. Furthermore, the crucial reasons that can promote the activities of composite solids by exsolution such as charge, lattice, orbit, and spin are discussed. Finally, the current challenges and further perspectives for constructing novel functional composite solids via exsolution are proposed.