The efficiency of splitting water into hydrogen and oxygen is highly dependent on the catalyst used. Herein, ultrathin Ni(0)‐embedded Ni(OH)₂ heterostructured nanosheets, referred to as Ni/Ni(OH)₂ nanosheets, with superior water splitting activity are synthesized by a partial reduction strategy. This synthetic strategy confers the heterostructured Ni/Ni(OH)₂ nanosheets with abundant Ni(0)‐Ni(II) active interfaces for hydrogen evolution reaction (HER) and Ni(II) defects as transitional active sites for oxygen evolution reaction (OER). The obtained Ni/Ni(OH)₂ nanosheets exhibit noble metal‐like electrocatalytic activities toward overall water splitting in alkaline condition, to offer 10 mA cm⁻² in HER and OER, the required overpotentials are only 77 and 270 mV, respectively. Based on such an outstanding activity, a water splitting electrolysis cell using the Ni/Ni(OH)₂ nanosheets as the cathode and anode electrocatalysts has been successfully built. When the output voltage of the electrolytic cell is 1.59 V, a current density of 10 mA cm⁻² can be obtained. Moreover, the durability of Ni/Ni(OH)₂ nanosheets in the alkaline electrolyte is much better than that of noble metals. No obvious performance decay is observed after 20 h of catalysis. This facile strategy paves the way for designing highly active non‐precious‐metal catalyst to generate both hydrogen and oxygen by electrolyzing water at room temperature.

中文翻译：

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超薄Ni（0）嵌入Ni（OH）2异质结构纳米片，具有增强的电化学总水分解性能

将水分解为氢气和氧气的效率高度取决于所使用的催化剂。本文中，通过部分还原策略合成了具有超强水分解活性的超薄Ni（0）嵌入Ni（OH）₂异质结构纳米片，称为Ni / Ni（OH）₂纳米片。这种合成策略赋予具有丰富的Ni（0）-Ni（II）活性界面的异结构Ni / Ni（OH）₂纳米片用于氢释放反应（HER）和Ni（II）缺陷作为氧释放反应的过渡活性位点（OER ）。所获得的Ni / Ni（OH）₂纳米片对碱性条件下的总水分解表现出贵金属样的电催化活性，可提供10 mA cm ^-2在HER和OER中，所需的超电势分别仅为77和270 mV。基于这种优异的活性，已经成功地构建了使用Ni / Ni（OH）₂纳米片作为阴极和阳极电催化剂的水分解电解槽。当电解池的输出电压为1.59V时，可获得10mA cm ^-2的电流密度。而且，Ni / Ni（OH）₂纳米片在碱性电解质中的耐久性比贵金属的耐久性好得多。催化20小时后未观察到明显的性能下降。这种简便的策略为设计高活性非贵金属催化剂铺平了道路，该催化剂通过在室温下电解水来产生氢气和氧气。