Metal/metal-oxide interface catalysed thermal and electrochemical CO conversion: a perspective from DFT-based studies.

Converting CO to valuable chemicals through a variety of thermal, photo-, and electro-catalytic reaction processes will reduce the net CO emission and contribute positively to the "net-zero" goal. C and C products are important chemical feedstocks and can be produced from the effective catalytic conversion of CO. The key to developing effective CO conversion catalysts is an understanding of CO interaction and the elementary bond-breaking and formation steps on the active catalysts. Over the past two decades, density functional theory-based approaches have enabled both mechanistic understanding and catalyst design for CO activation and conversion. In this article, we review our recent effort in understanding the mechanism of CO activation and conversion, focusing on the unique role of the metal/metal oxide interfaces in both thermal and electrochemical catalytic CO reduction. We showed that InO-based catalysts exhibited a uniquely high methanol selectivity while suppressing CO formation from the reverse water-gas shift reaction. We have also demonstrated that the metal/metal-oxide interfaces can be tuned by selecting an appropriate metal and metal oxide to optimize its activity and selectivity for both thermal- and electro-catalytic reduction of CO. The oxophilicity of the metal in the metal oxide can be used as a qualitative measure for determining the selectivity towards CHOH or CH in the electro-catalytic reduction of CO. The studies demonstrated the impact of the density functional theory-based atomic-level approaches in unravelling the reaction mechanism and predicting highly efficient catalysts and catalytic systems.