The development of efficient and earth‐abundant bifunctional electrocatalysts is of great important for energy conversion and storage technologies. Three surface oxidized nickel borides of Ni−B−O@Ni₃B, Ni−B−O@Ni₂B and Ni−B−O@NiB₂ electrocatalysts have been prepared and investigated. Surface oxidation, which is inevitable for the bifunctional nickel borides, promotes the activity for the oxygen evolution reaction (OER), but leads to activity degradation for the hydrogen evolution reaction (HER). Meanwhile, boron is found to play a crucial role in the oxidation of nickel, facilitating the formation of an active intermediate for the OER. Ni−B−O@Ni₃B turns out to be the best bifunctional electrocatalyst. An alkaline electrolyzer constructed using Ni−B−O@Ni₃B electrodes as both anode and cathode has achieved a current density of 10 mA cm⁻² at 1.58 V for overall water splitting with satisfied durability, rivaling the integrated noble metal electrode.

中文翻译：

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表面氧化的Ni3B，Ni2B和NiB2电催化剂的总水分解性能

开发高效且富含地球的双功能电催化剂对于能量转换和存储技术至关重要。制备并研究了Ni-B-O @ Ni ₃ B，Ni-B-O @ Ni ₂ B和Ni-B-O @ NiB ₂电催化剂的三种表面氧化的硼化镍。对于双官能硼化镍不可避免的表面氧化会提高氧释放反应（OER）的活性，但会导致氢释放反应（HER）的活性降低。同时，发现硼在镍的氧化中起关键作用，从而促进了OER活性中间体的形成。Ni-B-O @ Ni ₃B被证明是最好的双功能电催化剂。使用Ni-B-O @ Ni ₃ B电极作为阳极和阴极的碱性电解槽在1.58 V时实现了10 mA cm ^-2的电流密度，可实现整体水分解并具有令人满意的耐久性，可与集成的贵金属电极媲美。