近日，北京化工大学教授孙晓明及其课题组揭示了10000h稳定间歇式碱性海水电解。这一研究成果发表在2025年3月5日出版的国际学术期刊《自然》上。

本文首先揭示了间歇电解过程中海水分裂阴极的动态演化和降解过程，并在此基础上提出了构建催化剂钝化层来维持其运行过程中的析氢性能。在NiCoP-Cr₂O₃阴极表面原位形成的磷酸盐钝化层可以有效地保护金属活性位点在频繁放电过程中不被氧化，并在关闭条件下阻止阴极上的卤化物离子吸附。该课题组证明，采用这种设计策略优化的电极可以承受0.5 μ A / cm^-2的波动操作10000小时，电压增幅仅为0.5% khr^-1。新发现的挑战和他们提出的策略为促进可再生电力驱动的实用海水分解技术的发展提供了新的见解。

据介绍，由可再生电力驱动的海水电解为生产绿色氢提供了一个有吸引力的策略。然而，直接海水电解面临着许多挑战，主要是由于腐蚀和阳极上的竞争反应，这些反应是由大量的卤化物离子(Cl^-, Br^-)丰度引起。先前关于海水电解的研究主要集中在阳极的开发上，因为阴极在还原电位下工作，在海水电解过程中不受电极溶解或氯化物腐蚀反应的影响。然而，可再生能源的强度是间歇性的、可变的和随机的，如果以可再生电力为主题驱动海水电解，就会出现频繁的启停操作。

附：英文原文

Title: 10,000-h-stable intermittent alkaline seawater electrolysis

Author: Sha, Qihao, Wang, Shiyuan, Yan, Li, Feng, Yisui, Zhang, Zhuang, Li, Shihang, Guo, Xinlong, Li, Tianshui, Li, Hui, Zhuang, Zhongbin, Zhou, Daojin, Liu, Bin, Sun, Xiaoming

Issue&Volume: 2025-03-05

Abstract: Seawater electrolysis powered by renewable electricity provides an attractive strategy for producing green hydrogen1,2,3,4,5. However, direct seawater electrolysis faces many challenges, primarily arising from corrosion and competing reactions at the anode caused by the abundance of halide ions (Cl^-, Br^-) in seawater6. Previous studies3,6,7,8,9,10,11,12,13,14 on seawater electrolysis have mainly focused on the anode development, because the cathode operates at reducing potentials, which is not subject to electrode dissolution or chloride corrosion reactions during seawater electrolysis11,15. However, renewable energy sources are intermittent, variable and random, which cause frequent start–shutdown operations if renewable electricity is used to drive seawater electrolysis. Here we first unveil dynamic evolution and degradation of seawater splitting cathode in intermittent electrolysis and, accordingly, propose construction of a catalyst’s passivation layer to maintain the hydrogen evolution performance during operation. An in situ-formed phosphate passivation layer on the surface of NiCoP–Cr₂O₃ cathode can effectively protect metal active sites against oxidation during frequent discharge processes and repel halide ion adsorption on the cathode during shutdown conditions. We demonstrate that electrodes optimized using this design strategy can withstand fluctuating operation at 0.5Acm^-2 for 10,000h in alkaline seawater, with a voltage increase rate of only 0.5%khr^-1. The newly discovered challenge and our proposed strategy herein offer new insights to facilitate the development of practical seawater splitting technologies powered by renewable electricity.

DOI: 10.1038/s41586-025-08610-1

Source: https://www.nature.com/articles/s41586-025-08610-1