Dynamic Te–OH Proton Relay Enables Industrial‐Level Acidic CO ₂ Electroreduction on Single‐Atom Catalysts

Abstract

ABSTRACT Electrochemical CO 2 reduction reaction (CO 2 RR) in acidic media can suppress carbonate formation and boost CO 2 utilization efficiency. However, at high current densities, rapid proton consumption induces localized alkalization, causing insufficient proton supply and limiting reaction kinetics. Here we report a dynamic proton‐relay strategy that enables rapid and selective CO 2 RR by integrating atomically dispersed Ni–N sites on carbon with adjacent Te species (Ni–N/Te–C). The incorporated Te centers form reversible Te–OH/Te–O − couples that simultaneously promote water activation and mediate controlled proton delivery, thereby synchronizing hydrogen supply with intermediate protonation while suppressing competitive hydrogen evolution. As a result, Ni–N/Te–C achieves a CO Faradaic efficiency above 94.8% across a wide potential window from −0.8 to −1.4 V versus the reversible hydrogen electrode. Ni–N/Te–C delivers an industrial CO current density of 562.5 mA cm −2 and a turnover frequency of 16291.9 h −1 at −1.4 V, significantly higher than that of Ni–N/C. The catalyst also demonstrates remarkable durability, maintaining 93.8% selectivity for 300 h at 100.0 mA cm −2 . In situ spectroscopic characterization and theoretical calculations reveal that the Te–OH‐mediated proton relay modulates the reaction pathway of water dissociation and CO 2 protonation with significantly lower energy barriers, thus accelerating *COOH formation.