Catalytic Hydrogenation of CO2 to Formic Acid with Silica‐Tethered Iridium Catalysts

Tetherball: A heterogeneous, mesoporous silica-tethered iridium catalyst (Ir-PN/SBA-15) containing a bidentate iminophosphine ligand is synthesized for the hydrogenation of CO2 to formic acid in aqueous solution. This new recyclable catalyst exhibits high activities to formic acid production under mild conditions [60 °C, 4.0 MPa total pressure (H2/CO2=1:1)].