Charge‐Redistribution‐Driven Dual‐Single‐Atom Catalysts on MXene for Hydrogen Evolution

The hydrogen evolution reaction (HER) exhibits pH‐ and electrolyte‐dependent pathways, imposing intrinsic challenges on the development of catalysts that operate efficiently across wide pH conditions and in seawater electrolysis. Here, we report a dual‐single‐atom catalyst with proximate cooperative Pt and Ni sites on a MXene (Ti 3 C 2 T x ) platform that enables synergistic optimization of HER elementary steps. A one‐step molten salt‐assisted strategy, free of F‐based chemicals, allows the construction of high‐density, well‐dispersed Pt and Ni single atoms on MXene with well‐defined coordination environments. Atomic‐resolution microscopy and x‐ray absorption spectroscopy confirm the stabilization of isolated Pt and Ni sites, while in situ synchrotron‐based FTIR and DFT calculations reveal that proximate Ni sites modulate the electronic structure of Pt, weakening hydrogen adsorption and promoting water dissociation. As a result, the Pt SAs Ni SAs /Ti 3 C 2 T x delivers low overpotentials of 22.6 and 59.1 mV at 100 mA cm −2 in acidic and alkaline electrolytes, respectively, and maintains high activity in neutral electrolyte (282 mV) and alkaline seawater (73.2 mV) with stability up to 100 h, outperforming commercial 20% Pt/C. These findings demonstrate that leveraging the intrinsic surface chemistry of MXenes enables cooperative dual‐single‐atom architectures with synergistically optimized HER pathways, driven by inter‐site electronic coupling across diverse pH conditions.