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Updated: Jun 8, 2025
06:32
A Simple, Low-cost, and Robust System to Measure the Volume of Hydrogen Evolved by Chemical Reactions with Aqueous Solutions
Published on: August 17, 2016
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Unconventional Hexagonal Close-Packed High-Entropy Alloy Surfaces Synergistically Accelerate Alkaline Hydrogen
Ting-Hsin Hu1, Cheng-Yu Wu1, Zong Ying He2
1Department of Chemical Engineering, National Tsing Hua University, Hsinchu, 300044, Taiwan.
Advanced Science (Weinheim, Baden-Wurttemberg, Germany)
|November 8, 2024
Summary
Developing novel hexagonal close-packed (HCP) high-entropy alloy (HEA) atomic layers from platinum-group metals significantly boosts alkaline hydrogen evolution reaction (HER) performance and durability.
Area of Science:
- Materials Science
- Electrochemistry
- Catalysis
Background:
- The alkaline hydrogen evolution reaction (HER) is crucial for sustainable hydrogen production.
- Efficient HER catalysts require optimal binding of hydrogen (H*) and hydroxyl (OH*) intermediates.
- Cleavage of HO-H bonds and intermediate adsorption/desorption are rate-limiting steps.
Purpose of the Study:
- To develop novel catalysts for enhanced alkaline HER.
- To investigate the synergistic effects of high-entropy alloys (HEAs) in a hexagonal close-packed (HCP) structure.
- To understand the influence of atomic mixing on intermediate binding strengths.
Main Methods:
- Layer-by-layer heteroepitaxial deposition of subnanometer RuRhPdPtIr HEA layers on HCP Ru seeds.
- Synchrotron X-ray absorption spectroscopy (XAS) for structural and compositional analysis.
- Electrochemical measurements, operando XAS, and density functional theory (DFT) calculations.
Main Results:
- Successfully synthesized unconventional HCP HEA atomic layers (RuRhPdPtIr).
- HCP HEA catalysts demonstrated superior electrocatalytic activity and durability for alkaline HER compared to FCC counterparts.
- Atomic mixing in HCP HEA optimized H* and OH* binding strengths via synergistic electronic effects.
Conclusions:
- HCP HEA atomic layers offer a promising strategy for advanced alkaline HER electrocatalysts.
- Synergistic electronic effects from mixed elements in HCP HEA are key to improved catalytic performance.
- The study provides insights into catalyst design for efficient hydrogen production.
Keywords:
alkaline hydrogen evolutionatomic mixinghexagonal close‐packed structurehigh‐entropy alloyoperando X‐ray absorption spectroscopyMore Related Videos
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