Inhibiting Dissolution of Platinum with Atomic Rare Earth Bridged by Nitrogen to Boost Alkaline Hydrogen Evolution

Abstract The unfavorable water dissociation and continuous dissolution of Pt single‐atom catalysts significantly impede their practical application in alkaline anion exchange membrane water electrolyzers (AEMWEs). Herein, by integrating the electron‐buffer functionality of rare earth single atoms (RE = Pr, Ce, Gd, Sm) dispersed on N‐doped carbon substrates (N─C) with Pt single atoms, a novel catalyst Pt/RE‐N‐C is reported. The constructed Pt─N─Ce bridge causes electron enrichment on Pt sites and deficiency on RE sites, which favors adsorption of H_ads and OH_ads, respectively, and significantly promotes water dissociation. Meanwhile, the increased covalency of Pt─N bond inhibits detachment and thermal vibration of Pt atoms. As a representative, Pt/Ce─N─C requires an overpotential of only 22 mV to reach a current density of 10 mA cm⁻². The excellent mass activity of 7.16 A mg_Pt⁻¹ at an overpotential of 50 mV is 37.7 times higher than that of commercial Pt/C (0.19 A mg_Pt⁻¹). More importantly, the AEMWE with Pt/Ce─N─C (with a loading of only 32 µg_Pt cm⁻²) as the cathode catalyst exhibits an ultralow potential (1.79 V) and high stability at an industrial current density of 1.0 A cm⁻². This work demonstrates the advantages and potential of using RE single atoms for high‐efficient energy conversion.