Abstract
Developing noble-metal-free electrocatalyst for oxygen evolution reaction in a proton exchange membrane water electrolyzer is a key to sustainable and economical hydrogen production. Herein, we rationally design and develop a chromium and neodymium co-doped cobalt oxide (CrNd-Co3O4) electrocatalyst that exhibits high activity and durability in the acidic oxygen evolution reaction condition. Furthermore, an in-situ acid circulation strategy is proposed to tackle the ubiquitous issue of membrane poisoning by leached cations in proton exchange membrane water electrolyzers. Consequently, the proton exchange membrane water electrolyzer with CrNd-Co3O4 anode achieves a stable operating current density of 2 amperes per square centimeter at 2.27 volts and 4 amperes per square centimeter at 2.54 volts for 1,000 hours.
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Acknowledgements
This work was financially supported by a grant (CHI-P2022-04) from Centre for Hydrogen Innovations at National University of Singapore. B.L. acknowledges support from the City University of Hong Kong startup fund (9020003), ITF–RTH - Global STEM Professorship (9446006), and JC STEM Lab of Advanced CO2 Upcycling (9228005). H.T. thanks National Key R&D Program of China (2023YFB4004600), Science and Technology Projects (RD2021010401) of the Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), the Science and Technology Project (2022L3077) of Fujian Province, and the New Cornerstone Science Foundation. F.L. thanks the Fundamental Research Funds for the Central Universities, Southwest Jiaotong University (2682025CX062). S.-F.H. acknowledges financial support from the National Science and Technology Council, Taiwan (NSTC 114-2628-M-A49-005) and support from the Yushan Young Scholar Program and the Center for Emergent Functional Matter Science (Ministry of Education, Taiwan).
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B.L., P.C., H.T. and T.G. conceived and designed the project. T.G. performed the catalyst synthesis, most of the structural characterizations, and electrochemical tests. F.L. carried out the theoretical calculations. S.-F.H. and K.-S.P performed the XAS measurements. T.G. and H.T. conducted MEA preparation and PEMWE measurements. H.Y., Y.S., Q.S. and Q.M. assisted with data analysis and paper revision. T.G., P.C. and B.L. wrote the paper. All the authors reviewed and contributed to this paper.
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Gao, T., Li, F., Hung, SF. et al. Cr and Nd co-doped cobalt oxide for stable proton exchange membrane water electrolysis. Nat Commun (2026). https://doi.org/10.1038/s41467-026-71066-y
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DOI: https://doi.org/10.1038/s41467-026-71066-y
