Dynamic Reconstruction of Pt Gradient Doping in High-Entropy Alloys for Efficient Hydrogen Production

Hydrogen energy, as a zero-carbon energy carrier, urgently requires high-performance acidic hydrogen evolution reaction (HER) electrocatalysts. To address the challenges posed by costly Pt-based catalysts and the morphology-composition synergy in high-entropy alloys (HEAs), Pt_xFeCoNiCuMn (x = 0-34 at%) HEAs are developed using a multicomponent synergy design principle. Through the synergistic regulation of atomic radius matching and reduction potential gradients, dynamic morphological evolution from nanosheets (amorphous) → nanosheet-nanoparticle heterostructures → single-phase nanospheres (2.9 nm) is achieved via a low-temperature one-pot synthesis. Comprehensive characterization and theoretical analysis reveal a Pt-doping concentration-dependent regulation of HEAs morphology, lattice structure, and valence states. Experimental results demonstrate that the Pt₃₄FeCoNiCuMn HEA-NPs achieves exceptional HER performance in 0.5 m H₂SO₄, delivering an ultralow overpotential of η₁₀ = 5.1 mV, significantly outperforming commercial Pt/C (η₁₀ = 64.7 mV). This work establishes a quantitative "gradient doping-dynamic reconstruction-catalytic enhancement" structure-activity relationship model, providing theoretical guidance and novel strategies for the multiscale precision design of HEAs.