biostudies-literatureUnknown15(1)Yao ZThe electrocatalytic reduction of CO₂ to CO is slowed by the energy cost of the hydrogenation step that yields adsorbed *COOH intermediate. Here, we report a hydrogen radical (H•)-transfer mechanism that aids this hydrogenation step, enabled by constructing Ni-partnered hetero-diatomic pairs, and thereby greatly enhancing CO₂-to-CO conversion kinetics. The partner metal to the Ni (denoted as M) catalyzes the Volmer step of the water/proton reduction to generate adsorbed *H, turning to H•, which reduces CO₂ to carboxyl radicals (•COOH). The Ni partner then subsequently adsorbs the •COOH in an exothermic reaction, negating the usual high energy-penalty for the electrochemical hydrogenation of CO₂. Tuning the H adsorption strength of the M site (witNature communications9881https://www.ebi.ac.uk/biostudies/studies/S-EPMC11564623biostudies-literatureHydrogen radical-boosted electrocatalytic CO<sub>2</sub> reduction using Ni-partnered heteroatomic pairs.PMC11564623Xu LHao LXiong PYang MZhan XSun ZSoo YLYao ZTan XRobertson AWXu BLi MMCheng HWu TSXu YHong SfalseHydrogen radical-boosted electrocatalytic CO<sub>2</sub> reduction using Ni-partnered heteroatomic pairs.The electrocatalytic reduction of CO₂ to CO is slowed by the energy cost of the hydrogenation step that yields adsorbed *COOH intermediate. Here, we report a hydrogen radical (H•)-transfer mechanism that aids this hydrogenation step, enabled by constructing Ni-partnered hetero-diatomic pairs, and thereby greatly enhancing CO₂-to-CO conversion kinetics. The partner metal to the Ni (denoted as M) catalyzes the Volmer step of the water/proton reduction to generate adsorbed *H, turning to H•, which reduces CO₂ to carboxyl radicals (•COOH). The Ni partner then subsequently adsorbs the •COOH in an exothermic reaction, negating the usual high energy-penalty for the electrochemical hydrogenation of CO₂. Tuning the H adsorption strength of the M site (wit2024-01-01T00:00:00Z2024 Nov2025-04-21T22:15:49.785Z2025-04-05T18:40:40.995ZS-EPMC115646233954309110.1038/s41467-024-53529-2