Self-regeneration of supported transition metals by a high entropy-driven principle

Abstract

The sintering of Supported Transition Metal Catalysts (STMCs) is a core issue during high temperature catalysis. Perovskite oxides as host matrix for STMCs are proven to be sintering-resistance, leading to a family of self-regenerative materials. However, none other design principles for self-regenerative catalysts were put forward since 2002, which cannot satisfy diverse catalytic processes. Herein, inspired by the principle of high entropy-stabilized structure, a concept whether entropy driving force could promote the self-regeneration process is proposed. To verify it, a high entropy cubic Zr_0.5(NiFeCuMnCo)_0.5O_x is constructed as a host model, and interestingly in situ reversible exsolution-dissolution of supported metallic species are observed in multi redox cycles. Notably, in situ exsolved transition metals from high entropy Zr_0.5(NiFeCuMnCo)_0.5O_x support, whose entropic contribution (TΔS_config = T⋆12.7 J mol^-1 K^-1) is predominant in ∆G, affording ultrahigh thermal stability in long-term CO₂ hydrogenation (400 °C, >500 h). Current theory may inspire more STWCs with excellent sintering-resistance performance.