Exceptional CO2 Hydrogenation to Ethanol via Precise Single-Atom Ir Deposition on Functional P Islands

The thermocatalytic hydrogenation of CO₂ to ethanol has attracted significant interest because ethanol offers ease of transport and substantial value in chemical synthesis. Here, we present a state-of-the-art catalyst for the CO₂ hydrogenation to ethanol achieved by precisely depositing single-atom Ir species on P cluster islands situated on the In₂O₃ nanosheets. The Ir₁-P_x/In₂O₃ catalyst achieves an impressive ethanol yield of 3.33 mmol g⁻¹ h⁻¹ and a turnover frequency (TOF) of 914 h⁻¹ under 1.0 MPa (H₂/CO₂=3 : 1) at 180 °C, nearly 8 times higher than that of the unmodified Ir₁/In₂O₃ catalyst. Additionally, at a more industrially relevant pressure of 5.0 MPa, the TOF of the Ir₁-P_x/In₂O₃ catalyst can reach up to 2108 h⁻¹, surpassing previously reported catalysts. Combined in situ characterization and theoretical studies reveal that the hydrogenation process is significantly enhanced by the Ir₁-P_x entities. Specifically, the Ir atom facilitates CO₂ activation and C−C coupling, while the surrounding P island exhibits exceptional H₂ dissociation ability. These three steps have been found crucial for the CO₂ hydrogenation reaction. This discovery opens new opportunities for the regulation of the microenvironment of current catalysts by providing essential chemical functionalities that enhance intricate and complex reaction processes.