Designing transition metal-based heterointerfaces and creating defects are identified as prospective strategies for substituting the expensive noble metal-based catalysts for realizing efficient water electrocatalysis to alleviate the energy and environmental crisis. Herein, pleated sheet-like NiP-NiB-FeB heterostructure nanoarrays with three-phase heterojunctions and luxuriant defects were developed and grown on carbon cloth as effective self-supported bifunctional electrocatalysts for water-splitting by a facile one-step solution titration method. As expected, the NiP-NiB-FeB reveals remarkable electrocatalytic performance, requiring only 134 mV and 275 mV overpotentials to achieve the current density of 10 mA cm for HER and 100 mA cm for OER, respectively, whose performance exceeds most transition metal-based catalysts in previous reports. More encouragingly, the electrolyzer with NiP-NiB-FeB as a working electrode can attain a current density of 10 mA cm at a low voltage of 1.63 V accompanied by a long cycle stability of at least 36 h. The large specific surface area, abundant heterogeneous phase interfaces, and rich defective sites jointly contribute to the exposure of more active sites, regulation of the regional electron density, and promotion of the electrical conductivity, while the introduction of electronegativity P and electron-deficient B also imparts NiP-NiB-FeB with strong electronic interactions and fast charge transfer, thus endowing NiP-NiB-FeB with excellent catalytic activity. This work opens up new opportunities in multi-phase heterointerfaces and defects engineering of transition metal-based borides and phosphides as efficient multifunctional electrocatalysts for practical water splitting.

中文翻译：

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富缺陷Ni3P-NiB-FeB异质结构的制备作为高效双功能全水分解电催化剂

设计基于过渡金属的异质界面和制造缺陷被认为是替代昂贵的贵金属基催化剂以实现高效水电催化以缓解能源和环境危机的前瞻性策略。在此，通过一种简便的一步溶液滴定方法，在碳布上开发并生长了具有三相异质结和丰富缺陷的褶状片状NiP-NiB-FeB异质结构纳米阵列，作为有效的自支撑双功能水分解电催化剂。正如预期的那样，NiP-NiB-FeB表现出卓越的电催化性能，仅需要134 mV和275 mV的过电势即可分别实现10 mA cm的HER电流密度和100 mA cm的OER电流密度，其性能超过了大多数过渡金属基材料之前报告中的催化剂。更令人鼓舞的是，以NiP-NiB-FeB为工作电极的电解槽可以在1.63 V的低电压下达到10 mA cm的电流密度，并具有至少36 h的长循环稳定性。大的比表面积、丰富的异相界面和丰富的缺陷位点共同有助于暴露更多的活性位点，调节区域电子密度，提高电导率，同时引入电负性P和缺电子B还赋予 NiP-NiB-FeB 较强的电子相互作用和快速的电荷转移能力，从而赋予 NiP-NiB-FeB 优异的催化活性。这项工作为过渡金属基硼化物和磷化物的多相异质界面和缺陷工程开辟了新的机遇，作为实际水分解的高效多功能电催化剂。