Non‐noble metal‐based bifunctional electrocatalysts are highly desired for water electrolysis. However, constructing a water electrolyzer using a sole catalyst without compromising either its oxygen evolution reaction (OER) or hydrogen evolution reaction (HER) performance is still challenging. In this study, a simple strategy is developed to integrate 2 D and 0 D CoP in the same metal–organic framework precursor‐derived hollow N‐doped carbon nanotube‐assembled polyhedron (HNCNP). The unique hierarchical structure endows the resulting nanocomposite with both the advantages of more exposed active sites for 2 D and large surface‐to‐volume ratio for 0 D materials, whereas the hollow interior could benefit the charge and mass transfer properties. Thus, CoP/HNCNP@2 D CoP exhibits outstanding OER and HER activity and a low cell voltage when employed as both the anode and cathode in a two‐electrode water electrolyzer. The approach of integrating the same metal phosphide phase with diverse dimensions may inspire new ways to design hierarchical nanostructures for advanced energy conversion applications.

中文翻译：

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简单的2 D / 0 D CoP集成在金属有机框架衍生的双功能电催化剂中，可实现有效的总水分解。

水电解非常需要非贵金属双功能电催化剂。然而，在不损害其析氧反应（OER）或析氢反应（HER）性能的前提下，使用单一催化剂构造水电解槽仍然具有挑战性。在这项研究中，开发了一种简单的策略将2 D和0 D CoP集成在同一金属有机框架前驱体衍生的中空N掺杂碳纳米管组装多面体（HNCNP）中。独特的分层结构使所得的纳米复合材料具有以下优势：2 D的活性位点更暴露，0 D的材料的表面积与体积之比大，而中空内部则有利于电荷和传质。从而，CoP / HNCNP @ 2 D CoP在双电极水电解槽中同时用作阳极和阴极时，具有出色的OER和HER活性，并且电池电压低。整合具有不同尺寸的相同金属磷化物相的方法可能会激发出新的方法来设计用于高级能量转换应用的分层纳米结构。