Mo2B2O2MBene for Efficient Electrochemical CO Reduction to C2 Chemicals: Computational Exploration.

Emerging as a new class of two‐dimensional materials with atomically thin layers, MBenes have great potential for many important applications such as energy storage and electrocatalysis. Toward mitigating carbon footprint, there has been increasing interest in CO2/CO conversion on MBenes, but mostly focused on C1 products. C2+ chemicals generally possess higher energy densities and wider applications than C1 counterparts. However, C–C coupling is technically challenging because of high energy requirement and currently few catalysts are suited for this process. Here, we explore electrochemical CO reduction reaction to C2 chemicals on Mo2B2O2 MBene via density‐functional theory calculations. Remarkably, the most favorable CO–COH coupling is revealed to be a spontaneous and barrierless process, making Mo2B2O2 an efficient catalyst for C–C coupling. Among C1 and C2 chemicals, ethanol is predicted to be the primary product. Furthermore, by charge and bond analysis, it is unraveled that there exist significantly more unbonded electrons in the C atom of intermediate *COH than other C1 intermediates, which is responsible for the facile C–C coupling. From an atomic scale, this work provides microscopic insight into C–C coupling process and suggests Mo2B2O2 a promising catalyst for electrochemical CO reduction to C2 chemicals. [ABSTRACT FROM AUTHOR]