LAUSR

A series of efficient heterogenized ruthenium catalysts designated as Rux‐NHC‐MOF (x=1, 2, 3; NHC=N‐heterocyclic carbene; MOF=metal organic framework) were successfully synthesized by the immobilization of different ruthenium complexes RuCl3, [RuCp*Cl2]2 (Cp*=pentamethylcyclopentadienyl) and [Ru(C6Me6)Cl2]2 (C6Me6=hexamethylbenzene) on an azolium based MOF through post‐synthetic metalation. The heterogenized catalysts were subsequently accessed for the catalytic hydrogenation of CO2 to formic acid. The resulting Ru3‐NHC‐MOF catalyst exhibited the highest activity because of its stronger electron‐donating ability of C6Me6 ligand of [Ru(C6Me6)Cl2]2 complex, which is favorable for CO2 hydrogenation reaction. A high turnover number (TON) value up to 3803 was obtained at 120 °C under a total pressure of 8 MPa (H2/CO2=1) for 2 h with K2CO3 additive in N,N‐Dimethylformamide (DMF) solvent. Furthermore, the heterogenized Ru3‐NHC‐MOF catalyst was effectively recovered through filtration without significant loss of catalytic activity.