Efficient Cu3 clusters on MXene (Ti2CO2) for CO electroreduction

Abstract

Facilitating the carbon–carbon (CC) coupling process to convert carbon monoxide (CO) into high value-added hydrocarbons is currently a significant challenge for electrocatalysts. Herein, we demonstrate that sub-nano Cu clusters anchored on MXene (Ti₂CO₂) exhibit exceptional activity and selectivity for C₁ and C₂ hydrocarbons. Through comprehensive ab initio calculations, we identify sub-nano Cu clusters of an optimal size that consistently exhibit selectivity for methane (CH₄) and ethylene (C₂H₄) with overpotentials of 0.38 V and 0.43 V, respectively. These spatially confined sub-nano copper (Cu) clusters possess the ability to simultaneously adsorb multiple CO molecules, and d-p hybridization energy level shifts promotes the CC coupling process. Furthermore, the selectivity of these clusters can be modulated by the interaction between the clusters and the substrate. We elucidate the catalytic mechanism and the structure–activity relationship for these sub-nano Cu clusters with robust stability. These findings offer crucial insights into the atomic-level design of CO conversion into high-value chemicals and catalysts.