Reverse Sintering of Supported Metal Catalysts: Mechanisms and Applications

Metal nanoparticle sintering severely compromises catalyst longevity and atom efficiency in heterogeneous thermocatalysis. To counteract sintering, structural dynamics can be harnessed through surface redispersion and, in suitable exsolution systems, oxidative redissolution followed by re-exsolution to recover metal dispersion. This review establishes a comprehensive framework bridging these two phenomena through dynamic structural evolution and chemical potential variations. We systematically analyze their thermodynamic descriptors and kinetic variables, dissecting four redispersion pathways alongside advanced exsolution support architectures. Crucially, we highlight opportunities for cross-fertilization, discussing how redispersion protocols simplify exsolution catalyst regeneration and how exsolution principles inspire support defect engineering to construct stable, semi-embedded crater structures. To unlock these mechanisms, we evaluate how advanced in situ characterization and multiscale theoretical calculations quantitatively describe and predict these dynamic pathways and regulatory factors. Ultimately, scaling these dynamic reconstructions up to realistic industrial conditions coordinates a conceptual pivot toward engineering operational self-healing catalytic systems, unlocking novel frontiers for sintering mitigation.