CO2 hydrogenation to ethanol over Pt-Co3O4 catalysts: Effects of Pt promoter.

Direct hydrogenation of CO2 to ethanol is a promising approach for utilizing CO2. However, it still faces challenges such as lower selectivity and unclear C-C coupling mechanisms. In this work, we prepared Co3O4 catalysts and Pt-loaded Co3O4 catalysts (Pt-Co3O4) to investigate the influence of Pt on the properties of Co3O4 catalysts and the CO2 hydrogenation process. At 240°C and 3.2 MPa, the reduced 1wt. % Pt-Co3O4 catalyst showed 0.265 mmol/(g·h) ethanol yield, while the ethanol yield of the reduced Co3O4 catalyst was negligible. The characterization results revealed that the presence of Pt facilitated the regeneration of oxygen vacancies on the catalyst surface, leading to enhanced cycling performance. The in-situ DRIFTS results demonstrated that the *OCH3 generated on the Pt-Ov site underwent coupling with the *CH3 generated on the Co site, leading to ethanol production.