Rhodium Single‐Atom Catalyst Design through Oxide Support Modulation for Selective Gas‐Phase Ethylene Hydroformylation

A frontier challenge in single-atom (SA) catalysis is the design of fully inorganic sites capable emulating high reaction selectivity traditionally exclusive organometallic counterparts homogeneous catalysis. Modulating direct coordination environment SA sites, via exploitation oxide support's surface chemistry, stands as a powerful albeit underexplored strategy. We report that isolated Rh atoms stabilized on oxygen-defective SnO2 uniquely unite excellent TOF with essentially full gas-phase hydroformylation ethylene, inhibiting thermodynamically favored olefin hydrogenation. Density Functional Theory calculations and characterization suggest substantial depletion catalyst lattice oxygen, energetically facile SnO2, key to unlock pliability at mononuclear centers, leading an exceptional performance which par molecular catalysts liquid media.