Lattice-Confined Rh Single Atoms in SrTiO3 Enable Leaching-Resistant and Durable Heterogeneous Hydroformylation

Abstract Heterogeneous Rh catalysts hold great promise for olefin hydroformylation by integrating the catalytic efficiency of Rh with facile separation and recycling. However, achieving high catalytic activity together with long-term stability remains a formidable challenge because highly active Rh sites are prone to CO-induced carbonylation and subsequent metal leaching under reaction conditions. Here, we report a lattice-confinement strategy to construct a leaching-resistant Rh single-atom catalyst by incorporating isolated Rh atoms into the perovskite SrTiO3 (STO) framework for olefin hydroformylation. Comprehensive spectroscopic investigations and theoretical calculations reveal that Rh atoms are incorporated into the SrTiO3 lattice by partially replacing Ti4+ sites, generating electron-deficient Rhδ+ species stabilized by robust Rh-O(v)-Ti coordination and strengthened electronic metal-support interaction. This lattice-confined coordination environment regulates the electronic properties of Rh sites, weakens excessive Rh-CO interactions, and suppresses carbonyl-induced Rh leaching. Consequently, the catalyst exhibits high catalytic activity and selectivity toward hydroformylation of both simple and sterically demanding olefins, together with stable catalytic performance over 12 consecutive recycling runs without appreciable activity or selectivity decay. In contrast, conventional Rh single atoms dispersed on the SrTiO3 surface undergo rapid deactivation under identical reaction conditions, highlighting the critical role of lattice confinement in stabilizing Rh species. This work establishes lattice confinement as a general strategy for stabilizing dynamic single-atom sites under harsh catalytic environments.