【Frontiers in HaiChuan Chemical Technology】A team from Xi’an Jiaotong University has made significant progress in the field of catalysts for water electrolysis to produce hydrogen using anion exchange membranes

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Recently, the research team led by Researcher Zhao Xu from the School of Chemical Engineering and Technology at Xi’an Jiaotong University made significant progress in the field of catalysts for hydrogen production via anion-exchange membrane electrolysis. The relevant research findings were published in Nature Communications under the title \"Engineering Co-ion vacancies in dynamically reconstructed Co-based catalysts for practical anion-exchange membrane electrolysis\". This study proposes an innovative strategy for the electrochemical dynamic reconstruction of metal ion vacancies, enabling the precise creation of such vacancies in electrocatalysts under dynamic reconstruction conditions. It offers a new approach for developing high-performance, long-lasting catalysts for anion-exchange membrane water electrolysis for hydrogen production. Anion exchange membrane water electrolysis technology combines the low cost of alkaline electrolyzers with the high efficiency of proton exchange membrane electrolyzers, and represents an important approach for the large-scale production of green hydrogen in the future. However, the anodic oxygen evolution reaction tends to cause structural restructuring of the catalyst in highly corrosive environments, leading to a rapid decline in the activity of non-precious metal catalysts and severely restricting their practical application. How to balance the activity and stability of catalysts at high current densities has been a long-standing issue in this field. To address the aforementioned challenges, the research team led by Researcher Zhao Xu proposed an expandable electrochemical dynamic restructuring strategy for metal ion vacancies. By inducing the weakening of pre-catalyst bond strengths, hydroxyl oxides rich in metal ion vacancies can be formed during the dynamic restructuring process. These ion vacancies not only enhance covalency to promote lattice oxygen activation but also increase hydroxyl affinity to facilitate lattice oxygen refilling, effectively suppressing metal dissolution and structural collapse and thus ensuring the long-term stable operation of the catalyst. Thanks to the aforementioned structural advantages, the catalysts developed based on this strategy exhibit excellent performance in anion-exchange membrane electrolyzers. The hydrogen production current reaches 3.3 A cm-2 at 2 V, and after 1000 hours of continuous operation at 80°C and at an industrial-grade current density, the performance degradation rate is only 0.10 mV h-1, demonstrating outstanding stability under operational conditions. This study provides new insights for designing electrocatalysts with high activity and stability under high-current operating conditions, and is of great significance for advancing the industrialization of anion-exchange membrane water electrolysis for hydrogen production. The School of Chemical Engineering at Xi’an Jiaotong University is the first corresponding institution for this paper, and Zhao Jingxuan, a doctoral student at the same school, is the first author. This research was supported by the National Natural Science Foundation of China’s general/young researcher programs, Shaanxi Province’s Sanqin Talent Introduction Program, Shaanxi Province’s Qinchuangyuan High-Level Innovation and Entrepreneurship Talent Program, and Xi’an Jiaotong University’s Young Top-Talented Researchers Program. The Shared Experimental Center for Large-scale Instrumentation at Xi’an Jiaotong University provides support for relevant characterization and analysis.