Dual-Anion Entropy Engineering of Se-P High-Entropy Interfaces in HEAs for Optimized H^* Binding and Accelerated...

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• High-entropy alloys (HEAs) possess unique catalytic properties due to their complex composition and lattice structure.
• Current HEA electrocatalysts often lack interfacial tunability due to single-anionic components.

Purpose of the Study:

• To engineer a dual-anion interface in a multimetallic HEA for enhanced hydrogen evolution reaction (HER) catalysis.
• To investigate the synergistic effects of selenium and phosphorus integration on HEA catalytic performance.

Main Methods:

• Fabrication of a NiCoFeMnMo HEA precursor via hydrothermal synthesis.
• Solid-state phosphorization followed by hydrothermal selenization to create a P-in-bulk and Se-on-surface architecture.
• Electrochemical characterization and Density Functional Theory (DFT) calculations to assess HER activity and mechanism.

Main Results:

• The synthesized HEA-Se-P electrode demonstrated superior HER activity in 1.0 M KOH, achieving an overpotential of 17 mV at 10 mA·cm⁻².
• The dual-anion strategy created synergistic P-Se coordination and interfacial electronic disorder, optimizing catalytic turnover.
• Excellent long-term durability of the developed electrocatalyst was observed.

Conclusions:

• Entropy-driven dual-anion engineering is a highly effective strategy for designing advanced HEA electrocatalysts.
• The optimized interfacial ensemble with balanced hydrogen adsorption energetics significantly enhances HER performance.
• This approach offers a generalizable pathway for developing efficient catalysts for sustainable hydrogen production.