Crystal facet effect induced by different pretreatment of Cu2O nanowire electrode for enhanced electrochemical CO2 reduction to C2+ products

Electrocatalytic CO 2 conversion has been considered as a promising way to recycle CO 2 and produce sustainable fuels and chemicals. However, the efficient and highly selective electrochemical reduction of CO 2 directly into multi-carbon (C 2+ ) products remains a great challenge. Herein, we synthesized three type catalysts with different morphologies based on Cu 2 O nanowires, and studied their morphology and crystal facet reconstruction during the pre-reduction process. Benefiting from abundant exposure of Cu (100) crystal facet, the nanosheet structure derived Cu catalyst showed a high faradaic efficiency (FE) of 67.5% for C 2+ products. Additionally, electrocatalytic CO 2 reduction studies were carried out on Cu(100), Cu(110), and Cu(111) single crystal electrodes, which verified that Cu(100) crystal facets are favorable for the C 2+ products in electrocatalytic CO 2 reduction. Our work showed that catalysts would reconstruct during the CO 2 reduction process and the importance in morphology and crystal facet control to obtain desired products.