Cyclic (alkyl)(amino)carbene-copper supported on SBA-15 as an efficient and recyclable catalyst for CO2 hydrogenation to formate

Abstract

In recent years, copper-based catalysts have been widely studied in hydrogenation of CO2 to formic acid or formate. Although the advantages of low cost and low toxicity, the activity of copper-based catalysts is still not very satisfactory. In this work, CAAC cooper complex (CAAC-Cu) was supported on SBA-15 silica to give an efficient and recyclable catalyst SBA-15-CAAC-Cu for the hydrogenation of CO2 to formate. The ordered mesoporous structure of SBA-15 and the structure of CAAC-Cu have been preserved after functionalization. Using SBA-15-CAAC-Cu as catalyst, up to 4660 TON can be obtained at 100 °C, which is much better than homogeneous CAAC-Cu catalysts. In addition, the SBA-15-CAAC-Cu catalyst can be easily recycled multiple times without obvious loss in activity.