Electronic modulation of nickel via support interactions for enhanced electrochemical CO₂-to-ethanol conversion

Non-Cu electrocatalysts are rarely reported to generate multi-carbon (C 2 + ) products owing to the intrinsic scaling relationships between metal surfaces and intermediate binding strengths, as well as challenges in materials design. Herein, we synthesize a series of heteroatom-doped carbon (XC)-coated nickel (Ni) catalysts (Ni@XC, where X = B, P, N, or S) to demonstrate the influence of the dopant in the carbon overlayer on the intermediate binding strength on Ni, and consequently, on product selectivity. Among them, Ni@NC achieves an impressive ethanol (C 2 H 5 OH) faradaic efficiency of 60.3%, with a C 2 H 5 OH partial current density of 102 mA cm −2 at −0.5 V vs. the reversible hydrogen electrode in a flow cell using 1 M KOH electrolyte, while maintaining stable operation over 32 h. In situ Raman and CO stripping measurements reveal that *COOH and *CO serve as key intermediates, while NC overlayers enable a moderate CO binding strength on the Ni surface. Density functional theory (DFT) calculations reveal that N dopants modulate the Ni d-band centre, thereby regulating intermediate binding strength and promoting C 2 H 5 OH formation. ΔG *COOH-*OCCO (the energy difference between *COOH and *OCCO formation) is introduced as an efficient descriptor to quantify the balance between *COOH and *CO binding strengths, providing a mechanistic explanation for the superior C 2 H 5 OH activity on Ni@NC. This work underscores the vital role of surface engineering in modulating intermediate binding strength to enhance C 2 H 5 OH production on Ni-based catalysts, offering design insights for developing C 2+ products on non-Cu catalysts.