Direct seawater splitting is a promising strategy for the production of green hydrogen to address water shortage and environmental concerns. However, the primary obstacle in direct seawater splitting is directly related to the high selectivity and durability of oxygen evolution reaction (OER) electrocatalysts. In this study, we developed sulfur-doped multimetal (Ni, Fe, and Co) borophosphates (BPOs) as high-performance OER catalysts for alkalized seawater electrolytes. The incorporated sulfur atoms act as precursors to enhance the corrosion resistance, as they form negatively charged polyanionic surface layers that block the chloride ions. The best catalyst demonstrates an overpotential of 278 mV in alkaline freshwater and 292 mV in alkalized seawater electrolytes when subjected to a current density of 100 mA cm−2. The overpotential disparity between the two media was only 14 mV, suggesting that the material has substantial resistance to chloride corrosion. Furthermore, excellent electrochemical durability was attained for the sulfurized and amorphized multi-metal BPOs, highlighting their high potential as promising catalysts for seawater oxidation.

中文翻译：

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S 掺杂无定形多金属硼磷酸盐，用于高效的碱性海水氧化，具有高耐腐蚀性


直接海水分解是生产绿色氢气以解决水资源短缺和环境问题的一种很有前途的策略。然而，直接海水分解的主要障碍与析氧反应 （OER） 电催化剂的高选择性和耐久性直接相关。在这项研究中，我们开发了硫掺杂多金属（Ni、Fe 和 Co）硼磷酸盐 （BPO） 作为碱化海水电解质的高性能 OER 催化剂。掺入的硫原子作为前驱体，增强耐腐蚀性，因为它们形成带负电荷的聚阴离子表面层，阻断氯离子。当电流密度为 100 mA cm-2 时，最佳催化剂在碱性淡水中表现出 278 mV 的过电位，在碱化海水电解质中表现出 292 mV 的过电位。两种介质之间的过电位差仅为 14 mV，表明该材料具有很强的抗氯化物腐蚀能力。此外，硫化和非晶化多金属 BPO 获得了优异的电化学耐久性，突出了它们作为海水氧化催化剂的巨大潜力。