Scalable Ni‑driven synthesis of Pt single‑site catalysts for hydrogen evolution

Low-platinum-loading electrocatalysts, offering both high activity and durability under practical conditions, are essential for sustainable hydrogen production. Here we report a scalable synthesis of a platinum single-site catalyst supported on Ni-N-doped carbon nanotubes, achieved via a facile Ni-driven one-step reduction-displacement of Pt⁴⁺. The catalyst NCNT-Ni/Pt features a N₂-Pt-Cl₂ initial coordination, where the dynamic evolution of Pt-Cl bonds regulates the hydrogen evolution reaction performance. Excitingly, the catalyst demonstrates an overpotential of 7.78 ± 0.86 mV at 10 mA cm^-2. With a Pt loading of 6 μg cm^-2, it enables industrially relevant proton exchange membrane water electrolysis at 1.63 V@1 A cm^-2, with a degradation rate of 3.3 μV h^-1, sustained over 4500 h. Coupled with a 21%-efficient photovoltaic module, it delivers a 16.06% solar-to-hydrogen efficiency at industrial-level current density. This study presents a practical strategy for minimizing precious-metal use in the synthesis of industrial-grade hydrogen evolution electrocatalysts.