Proton Capture Strategy for Enhancing Electrochemical CO2 Reduction on Atomically Dispersed Metal–Nitrogen Active Sites**

Abstract Electrocatalysts play a key role in accelerating the sluggish electrochemical CO 2 reduction (ECR) involving multi‐electron and proton transfer. We now develop a proton capture strategy by accelerating the water dissociation reaction catalyzed by transition‐metal nanoparticles (NPs) adjacent to atomically dispersed and nitrogen‐coordinated single nickel (Ni−N x ) active sites to accelerate proton transfer to the latter for boosting the intermediate protonation step, and thus the whole ECR process. Aberration‐corrected scanning transmission electron microscopy, X‐ray absorption spectroscopy, and calculations reveal that the Ni NPs accelerate the adsorbed H (H ad ) generation and transfer to the adjacent Ni−N x sites for boosting the intermediate protonation and the overall ECR processes. This proton capture strategy is universal to design and prepare for various high‐performance catalysts for diverse electrochemical reactions even beyond ECR.