Synergistic P/Co Modulation of Pt Electronic Structure for Efficient Hydrogen Evolution via Seawater Electrolysis

Although Co modulation can optimize the electronic structure of Pt for hydrogen evolution reaction (HER), PtCo still suffers from chloride ion (Cl^-) corrosion in seawater electrolysis, severely limiting its practical applications. This study successfully constructed P-doped PtCo nanoflowers (P-PtCo NFs) with excellent corrosion resistance and rapid water dissociation kinetics through the introduction of P for synergistic electronic regulation. To demonstrate, the P-PtCo NFs require only an 18.2 mV overpotential to achieve 10 mA cm^-2 in alkaline seawater, which is significantly lower than those of PtCo NFs (43.2 mV) and commercial Pt/C (65.2 mV), and maintain stable operation for over 500 h in 1 M KOH. X-ray photoelectron spectroscopy and density functional theory analyses reveal strong electron interaction between P atoms and PtCo, which downshifts the d-band center of Pt by 0.038 eV and optimizes the adsorption strength of active sites toward hydrogen intermediates. In situ Raman spectroscopy and CO stripping experiments further illustrate that P doping reconstructs the electronic distribution of Pt, effectively promoting water molecule dissociation. This work highlights the essential role of P in conferring both corrosion resistance and fast reaction kinetics, providing a design strategy for efficient and durable seawater electrolysis catalysts through multicomponent electronic synergism.