Efficient CO₂ Electroreduction to Multicarbon Products at CuSiO₃/CuO Derived Interfaces in Ordered Pores

Abstract

Electrochemical CO₂ conversion to value-added multicarbon (C₂₊) chemicals holds promise for reducing CO₂ emissions and advancing carbon neutrality. However, achieving both high conversion rate and selectivity remains challenging due to the limited active sites on catalysts for carbon-carbon (C─C) coupling. Herein, porous CuO is coated with amorphous CuSiO₃ (p-CuSiO₃/CuO) to maximize the active interface sites, enabling efficient CO₂ reduction to C₂₊ products. Significantly, the p-CuSiO₃/CuO catalyst exhibits impressive C₂₊ Faradaic efficiency (FE) of 77.8% in an H-cell at -1.2 V versus reversible hydrogen electrode in 0.1 M KHCO₃ and remarkable C₂H₄ and C₂₊ FEs of 82% and 91.7% in a flow cell at a current density of 400 mA cm^-2 in 1 M KOH. In situ characterizations and theoretical calculations reveal that the active interfaces facilitate CO₂ activation and lower the formation energy of the key intermediate *OCCOH, thus promoting CO₂ conversion to C₂₊. This work provides a rational design for steering the active sites toward C₂₊ products.