Dimensional effect of oxide-derived Cu electrocatalysts to reduce CO2 into multicarbon compounds

Abstract

Oxide-derived Cu (OD-Cu) are the most promising catalysts for multicarbon formation via CO2 electroreduction (CO2ERR), yet facing structural/compositional reconstruction trends during CO2ERR. Nanocatalysts with specific mesoscopic morphology are more resistant to reconstruction, which would benefit systematical exploration of dimensional effects on CO2ERR. Herein, nanostructured OD-Cu catalysts of 1D nanowires (NWs), 2D nanosheets (NSs) and 3D nanoflowers (NFs) with good reconstruction resistance during CO2ERR are fabricated. Their well-preserved dimensional structures lead to altered Cu–O coordination, which is intensively investigated via X-ray absorption fine structure spectroscopy, resulting in distinctive CO2ERR performances. OD-Cu NWs catalyst with the highest Cu–O coordination possesses an impressive 77.7 % C2+ faradaic efficiency. Further in situ Fourier-transformed infrared spectroscopy and density functional theory calculations suggest more favorable asymmetric C–C coupling over the highest Cu–O coordination surface of OD-Cu NWs. This work provides new insights on developing reconstruction-resistant OD-Cu catalysts for value-added chemicals from advanced CO2 conversion.