Two-dimensional van der Waals heterojunctions (2D vdWHs) have received significant attention owing to their extraordinary properties such as the reduced energy barriers and efficient charge transfer. However, there is limited research about the construction of 2D vdWHs in electrocatalysts for improving multifunctional performance. Herein, we report a sandwich-like structured Co-MOF/TiN/NC-240 electrocatalyst with 2D vdWHs by one-step high-temperature solid-state and room-temperature ultrasonication methods, with 2D Co-MOF nanosheets uniformly assembled on the TiN/NC substrate. Ultraviolet Photoelectron Spectroscopy (UPS) reveal that the work function difference between Co-MOF and TiN/NC drives electron transfer from TiN/NC to Co-MOF, thereby modulating the metal oxidation state. The Co-MOF/TiN/NC-240 electrocatalyst exhibits boosted trifunctional electrocatalytic performances for ORR, OER, and HER, which can be attributed to the successful construction of 2D vdWHs, inducing effective electron redistribution via the heterogeneous interface and increasing the number of active sites. Moreover, the zinc-air battery (ZAB) and water-splitting device based on Co-MOF/TiN/NC-240 exhibit enhanced discharge capacity and superior efficiency, respectively. This study not only provides an effective design strategy to develop trifunctional electrocatalysts by constructing 2D vdWHs but also offers valuable insights into the enhanced electrocatalytic performance in the sustainable energy field.

中文翻译：

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通过二维范德华异质结的电子再分布促进了三明治式结构化 Co-MOF/TiN/NC 复合材料中的三官能电催化

二维范德华异质结 （2D vdWHs） 因其非凡的特性而受到广泛关注，例如减少能量势垒和高效的电荷转移。然而，关于在电催化剂中构建 2D vdWHs 以提高多功能性能的研究有限。在此，我们通过一步高温固态和室温超声方法报道了一种具有 2D vdWHs 的三明治状结构 Co-MOF/TiN/NC-240 电催化剂，其中 2D Co-MOF 纳米片均匀组装在 TiN/NC 衬底上。紫外光电子能谱 （UPS） 揭示了 Co-MOF 和 TiN/NC 之间的功函数差异驱动电子从 TiN/NC 转移到 Co-MOF，从而调节金属氧化态。Co-MOF/TiN/NC-240 电催化剂对 ORR、OER 和 HER 表现出增强的三功能电催化性能，这可归因于成功构建 2D vdWHs，通过异质界面诱导有效的电子重新分布并增加活性位点的数量。此外，基于 Co-MOF/TiN/NC-240 的锌空气电池 （ZAB） 和分解水装置分别表现出增强的放电容量和卓越的效率。本研究不仅为通过构建 2D vdWHs 开发三功能电催化剂提供了一种有效的设计策略，而且为可持续能源领域增强的电催化性能提供了有价值的见解。