Stimulating Efficiency for Proton Exchange Membrane Water Splitting Electrolyzers: From Material Design to Electrode Engineering

Abstract

Proton exchange membrane water electrolyzers (PEMWEs) are a promising technology for large-scale hydrogen production, yet their industrial deployment is hindered by the harsh acidic conditions and sluggish oxygen evolution reaction (OER) kinetics. This review provides a comprehensive analysis of recent advances in iridium-based electrocatalysts (IBEs), emphasizing novel optimization strategies to enhance both catalytic activity and durability. Specifically, we critically examine the mechanistic insights into OER under acidic conditions, revealing key degradation pathways of Ir species. We further highlight innovative approaches for IBE design, including (i) morphology and support engineering to improve stability, (ii) structure and phase modulation to enhance catalytic efficiency, and (iii) electronic structure tuning for optimizing interactions with reaction intermediates. Additionally, we assess emerging electrode engineering strategies and explore the potential of non-precious metal-based alternatives. Finally, we propose future research directions, focusing on rational catalyst design, mechanistic clarity, and scalable fabrication for industrial applications. By integrating these insights, this review provides a strategic framework for advancing PEMWE technology through highly efficient and durable OER catalysts.

Graphical Abstract

In order to realize the efficient application of the industrial PEMWEs, material design strategies for stimulating the activity and stability capability of OER electrocatalysts are summarized, including (i) morphology/support effects, (ii) structure/phase engineering, (iii) electronic configuration/interaction. Furthermore, the reaction mechanism is deeply clarified, and electrode engineering and challenges of IBEs in practical PEMWE application are focused.

Keywords

Iridium-based electrocatalysts / Oxygen evolution reaction / Activity and stability / Water electrolysis / Hydrogen energy

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Funding

National Natural Science Foundation of China(21875039)

Pilot Group Program of the Research Fund for International Senior Scientists(22250710676)

central government guides local funds for scientific and technological development(2021Szvup084)

Engineering and Physical Sciences Research Council(EPSRC)

UK Research and Innovation (UKRI) under the UK government‘s Horizon Europe funding(101077226)

EPSRC Centre for Doctoral Training in Molecular Modelling and Materials Science(EP/L015862/1)

RIGHTS & PERMISSIONS

The Author(s)