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Updated: Aug 11, 2026
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Hydrogen Production and Utilization in a Membrane Reactor
Published on: March 10, 2023
Decouple Intrinsic Activity and Mass Transfer Optimization to Achieve Ultra-High Hydrogen Evolution Reaction
Xuejiang Zhang1, Yongsheng Wang1, Mengting Chen1
1State Key Lab of Organic-Inorganic Composites and Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing100029, China.
ACS Applied Materials & Interfaces
|August 9, 2026
Summary
Mass transfer, not intrinsic activity, limits platinum-based catalysts for the hydrogen evolution reaction (HER). A novel nanorod array substrate significantly enhances HER performance and stability in water electrolyzers.
Area of Science:
- Electrochemistry
- Materials Science
- Catalysis
Background:
- Proton exchange membrane water electrolyzers (PEMWEs) require efficient hydrogen evolution reaction (HER) catalysts.
- Platinum (Pt) catalysts are effective but costly, necessitating performance optimization.
- Understanding overpotential origins is key to designing advanced HER catalysts.
Purpose of the Study:
- To investigate the factors limiting HER performance on Pt/C catalysts.
- To develop a novel catalyst structure for enhanced HER activity and stability.
- To elucidate the mechanism behind improved mass transfer in the new catalyst system.
Main Methods:
- Electrochemical characterization of Pt/C and Pt/CoP-NRA catalysts.
- Synthesis of Pt nanoparticles on a Cobalt Phosphide (CoP) nanorod array substrate (Pt/CoP-NRA).
- Long-term chronoamperometric testing to assess stability.
- Mechanism study focusing on bubble detachment and mass transfer.
Main Results:
- Mass transfer, not intrinsic activity, was identified as the dominant overpotential source for Pt/C at higher loadings.
- Pt/CoP-NRA catalysts demonstrated significantly higher mass activity (5.4x) compared to Pt/C.
- Ultra-low Pt loading on Pt/CoP-NRA achieved high performance.
- Negligible degradation was observed over 1000 hours of operation at 500 mA cm-2.
- Nanorod array substrates enhanced bubble detachment, improving mass transfer.
Conclusions:
- Optimizing mass transfer is crucial for improving HER performance in PEMWEs.
- Pt/CoP-NRA represents a highly efficient and stable HER catalyst with reduced Pt utilization.
- The nanorod array architecture effectively mitigates mass transfer limitations by facilitating bubble removal.
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