Density Functional Theory Study of CO(2) Hydrogenation on Transition-Metal-Doped Cu(211) Surfaces

The massive emission of CO(2) has caused a series of environmental problems, including global warming, which exacerbates natural disasters and human health. Cu-based catalysts have shown great activity in the reduction of CO(2), but the mechanism of CO(2) activation remains ambiguous. In this work, we performed density functional theory (DFT) calculations to investigate the hydrogenation of CO(2) on Cu(211)-Rh, Cu(211)-Ni, Cu(211)-Co, and Cu(211)-Ru surfaces. The doping of Rh, Ni, Co, and Ru was found to enhance CO(2) hydrogenation to produce COOH. For CO(2) hydrogenation to produce HCOO, Ru plays a positive role in promoting CO dissociation, while Rh, Ni, and Co increase the barriers. These results indicate that Ru is the most effective additive for CO(2) reduction in Cu-based catalysts. In addition, the doping of Rh, Ni, Co, and Ru alters the electronic properties of Cu, and the activity of Cu-based catalysts was subsequently affected according to differential charge analysis. The analysis of Bader charge shows good predictions for CO(2) reduction over Cu-based catalysts. This study provides some fundamental aids for the rational design of efficient and stable CO(2)-reducing agents to mitigate CO(2) emission.