In Situ Reconstruction of Cu–N Coordinated MOFs to Generate Dispersive Cu/Cu₂O Nanoclusters for Selective Electroreduction of CO₂to C₂H₄

Abstract

Electrochemical reduction of CO2 to obtain high-value-added feedstocks is a promising strategy to alleviate the energy crisis. Cu-based catalysts generate multi-carbon products with high activity in the CO2 reduction reaction (CO2RR), although great challenges remain in the selectivity and stability of Cu-based catalysts. Here, highly active Cu/Cu2O nanoclusters were produced via in situ electrochemical reconstruction using Cu–N coordinated MOFs as precursors for the highly selective C2H4 synthesis, showing a Faradaic efficiency of 70.2 ± 1.7% toward C2H4 with a partial current density of 12.38 mA·cm–2 at −1.03 V vs RHE in the CO2RR. In situ infrared spectroscopy with the observation of *CO*CO and *CO*COH intermediates confirmed the C2H4 formation pathway, while in situ Raman spectroscopy, ex situ XPS, and HRTEM evidenced that the coexisting Cu2O and Cu nanoclusters were the active sites. The in situ reconstruction method could be used to synthesize catalysts with high activity and selectivity for CO2 electroreduction.