Abstract In order to improve the efficiency of the water splitting system, many researchers have focused on controlling the nanostructure of the catalysts, which could reduce the overpotential value of the overall water splitting process. Herein, we report the characteristics of the overall water splitting of cobalt nitrides synthesized in the same way but differing only in the temperature of nitridation. Hierarchical phases (Co3N, Co3N/Co4N, and Co4N) and structures (mesoporous nanocubes, porous nanocubes, and aggregated particles) of CoxN with different thickness of amorphous N-doped carbon allowed CoxN to have different overpotential values (419 mV, 557 mV, and 606 mV at a current density of 10 mA∙cm−2), which is in contrast to known theoretical electrical properties. Our research about the comparison of hierarchical structure of CoxN offers the potential as advanced electrocatalysts for many materials that have not yet been morphologically controlled.

中文翻译：

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具有 3D 介孔结构和用于整体水分解的无定形 N 掺杂碳的形态可调 CoxN

摘要 为了提高水分解系统的效率，许多研究人员将注意力集中在控制催化剂的纳米结构上，这可以降低整个水分解过程的过电位值。在此，我们报告了以相同方式合成的氮化钴的整体水分解特性，但仅在氮化温度上有所不同。具有不同厚度的无定形氮掺杂碳的 CoxN 的分层相（Co3N、Co3N/Co4N 和 Co4N）和结构（介孔纳米立方体、多孔纳米立方体和聚集颗粒）允许 CoxN 具有不同的过电位值（419 mV、557 mV、在 10 mA∙cm−2 的电流密度下为 606 mV），这与已知的理论电特性相反。