Hierarchical nanostructures with unique synergistic electronic effects and abundant active sites play an essential role in the field of electrocatalysis. In this work, 1D@2D hierarchical NiCo₂O₄@MIL-53(Fe) nanostructures are constructed via introducing MIL-53(Fe) over NiCo₂O₄ nanoneedles grown on nickel foam [NiCo₂O₄@MIL-53(Fe)]. NiCo₂O₄@MIL-53(Fe) exhibits high catalytic activity of the oxygen evolution reaction due to the strong electronic interaction between NiCo₂O₄ and MIL-53(Fe), as well as the hierarchical nanostructures that provide numerous active sites. In 1.0 M KOH, the NiCo₂O₄@MIL-53(Fe) can achieve the current densities of 10 and 100 mA cm^–2 with overpotentials of only 231 and 260 mV, respectively; the hierarchical catalysts show good electrochemical and structural stability, operating for more than 100 h at a current density of 10 mA cm^–2 without obvious decay.

中文翻译：

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1D@2D分级NiCo2O4@MIL-53(Fe)纳米结构协同增强析氧反应

具有独特协同电子效应和丰富活性位点的多级纳米结构在电催化领域发挥着重要作用。在这项工作中，通过_在镍泡沫[NiCo ₂ O ₄ @MIL- _{53 (}铁）]。由于NiCo ₂ O ₄和MIL-53(Fe)之间的强电子相互作用以及提供大量活性位点的分层纳米结构，NiCo ₂ O ₄ @MIL-53(Fe)表现出较高的析氧反应催化活性。在1.0 M KOH中，NiCo ₂ O _{4 @MIL-53(Fe)可实现10和100 mA cm} ^–2的电流密度，过电势分别仅为231和260 mV；该多级催化剂表现出良好的电化学和结构稳定性，在10 mA cm ^–2的电流密度下运行超过100 h，没有明显的衰减。