UiO-66-derived carbon-confined PtZn alloy catalysts: synergistic electronic structure regulation and enhanced hydrogen evolution performance.

Reducing Pt usage while maintaining high activity and durability remains a central challenge for acidic hydrogen evolution reaction (HER) electrocatalysts. Here, we report a confinement-alloying strategy that integrates PtM-u (M = Zn, Co, and Ru) alloy nanoparticles within a hierarchically porous carbon scaffold derived from the controlled pyrolysis of UiO-66. The resulting catalysts exhibit markedly enhanced HER performance in acidic media compared to commercial PtC. Notably, the PtZn-u catalyst demonstrates exceptional intrinsic activity, achieving an overpotential of only 10 mV at 10 mA cm-2 and a Tafel slope of 44.1 mV dec-1, alongside robust long-term durability. Mechanistic investigations reveal that the carbon framework effectively suppresses nanoparticle migration and agglomeration, while Zn alloying modulates the electronic structure of Pt to optimize hydrogen binding. This work establishes the synergistic regulation of support confinement and the alloying effect as an effective design paradigm for high-performance, low-Pt HER electrocatalysts.