High-Performance M_aZrO_<i>x</i> (M_a = Cd, Ga) Solid-Solution Catalysts for CO₂ Hydrogenation to Methanol

Abstract

Hydrogenation of CO2 to methanol utilizing the hydrogen from renewable energy sources offers a promising way to reduce CO2 emissions through the CO2 utilization as a carbon source. However, it is a challenge to convert CO2 to methanol with high activity and high methanol selectivity. Herein, we report a class of metal-oxide solid-solution catalysts: MaZrOx (Ma = Cd, Ga), which show a methanol selectivity up to 80% with the CO2 single pass conversion reaching 4.3%–12.4% under the reaction conditions of H2/CO2 = 3/1, 24 000 h–1, 5 MPa. Structural and electronic characterizations combined with denisty functional theory calculations suggest that the Ma and Zr components in MaZrOx (Ma = Cd, Ga) solid-solution catalysts show a strong synergetic effect, which enhances the H2 heterolytic dissociation and results in high activity and high methanol selectivity. The solid-solution catalyst with dual metal oxide components offers an approach for the selective hydrogenation of CO2 to chemicals.