Although modulating the d-band center (εd) is an effective strategy to improve electrocatalytic activity, precise regulation of εd for CO2 electroreduction to CO remains a substantial challenge. Here, we report a heterostructured catalyst consisting of In2O3-incorporated 3D nanowire copper foam (Cu2O/In2O3@CF), with tunable εd via Cu-O-In bridges for efficient electrocatalytic CO2 reduction (eCO2R) to CO. The optimized Cu2O/In2O3@CF delivers impressive CO Faradaic efficiency (FECO) exceeding 90% over a broad potential range from -0.47 to -0.87 V (vs. reversible hydrogen electrode, RHE), with a peak FECO of 95.8% at -0.67 V (vs. RHE), and a high production rate of 1035.3 µmol cm-2 h-1, along with stable operation for over 130 h. In situ Raman and Fourier transform infrared spectroscopy (FTIR) analyses combined with density functional theory (DFT) calculations reveal that the formation of Cu2O/In2O3 heterointerface with Cu-O-In bridge facilitates charge redistribution, upshifting the εd of Cu sites and downshifting that of In sites, thereby optimizing the adsorption-desorption energies of reaction intermediates during eCO2R. This synergistic design of oxide-oxide heterointerface with an interconnected 1D nanowires architecture offers an innovative strategy for enhancing eCO2R performance.
Xiao et al. (Sat,) studied this question.