Supported Cu cluster on N-doped graphene: An efficient triatom catalyst for CO electroreduction to propanol at low potential.

Electroreduction of carbon monoxide into high-energy fuel is an excellent energy strategy for sustainable development, but the high yield of multi-carbon products remains a difficult challenge. Inspired by the successful synthesis of various trimer metal clusters and studies on electrocatalysis of CO to C3 products by Cu-based catalysts, Cu supported on N-doped graphene structures (Cu@NG) are investigated as electrocatalysts for CORR toward propanol in this paper. Due to the appropriate Cu-Cu bond length, the moderate charge of the Cu site, mild CO adsorption energy, and 100 % CO coverage, the absorbed 3*CO substance can form the critical *CO-CO-CO intermediate with a rather low kinetic barrier of 0.25 eV. The limiting potential of the whole process for the formation of propanol is just -0.15 V. Our work not only showed that Cu@NG is an excellent catalyst for the formation of propanol with high selectivity at low potential but also indicated that the *CO coverage can greatly reduce the CO hydrogenation potential and bonding of some intermediates such as *CHO. This research will provide a new idea for the material design of products tending to multi-carbon.