Interfacial confinement of ultra-low Pt single atoms via Co–Pt–C/N electronic bridging for efficient hydrogen evolution

Abstract

Developing highly efficient electrocatalysts with minimal noble metal usage for the hydrogen evolution reaction (HER) remains a critical challenge. Herein, we report a “confinement-to-interface” synthetic strategy to construct a novel single-atom catalyst. In this architecture, cobalt nanoparticles (Co_NP) act as “metal islands” on a conductive carbon scaffold, while platinum single atoms (Pt_SA) with a low loading of 1.35 wt% are precisely anchored at their interface via engineered Co–Pt–C/N interfacial bridging (Pt_SACo_NP/CN). This unique architecture, achieved through dual-confinement engineering (spatial and chemical), ensures exceptional dispersion and stability of the Pt sites and activates strong electronic coupling between Pt and Co. Consequently, the catalyst exhibits outstanding HER performance with ultralow overpotentials of 8 mV in acidic electrolyte and 18 mV in alkaline electrolyte at 10 mA cm⁻², along with robust stability exceeding 40 hours in both electrolytes. This work offers a new paradigm for atom-economical design of efficient and low-cost electrocatalysts through atomic-level bridging engineering, providing a promising path for sustainable hydrogen production.