Metal–organic framework-derived cupric oxide polycrystalline nanowires for selective carbon dioxide electroreduction to C2 valuables

Abstract

Carbon dioxide (CO₂) electroreduction is promising for balancing the carbon cycle for a sustainable society. However, an efficient electrocatalyst is the key to selectively converting CO₂ and generating valuable products. In this work, metal–organic framework (MOF) derived porous cupric oxide nanowires are prepared by a controllable annealing method for the efficient CO₂ reduction. These polycrystalline nanocatalysts demonstrate a high Faradaic efficiency (FE) of ∼70% for C2 products at −1.3 V vs. RHE. A partial current density of ∼141 mA cm⁻² for ethylene with a FE of ∼37% is achieved in a home-made flow cell at −1.3 V vs. RHE. The in situ/ex situ investigations indicate that the oxide-derived metallic copper with abundant interfaces would be the real active sites for highly selective CO₂ electrolysis. This work offers effective copper catalysts to selectively convert CO₂ toward valuable products, and more importantly provides insightful understanding of developing efficient catalytic materials for energy conversion.