Self-Reconstructed Two-Dimensional Cluster-Based Co–Organic Layer Heterojunctions for Enhanced Oxygen Evolution Reactions

Abstract

When it comes to an efficient catalytic oxygen evolution reaction (OER) in the production of renewable energy and chemicals, the construction of heterogeneous structures is crucial to break the linear scalar relationship of a single catalyst. This heterogeneous structure construction helps creatively achieve high activity and stability. However, the synthesis process of heterogeneous crystalline materials is often complex and challenging to capture and reproduce, which limits their application. Here, the dynamic process of structural changes in Co-MOFs in alkali was captured by in situ powder X-ray diffraction, FT-IR spectroscopy, and Raman spectroscopy, and several self-reconfigured MOF heterogeneous materials with different structures were stably isolated. The created β-Co­(OH)2/Co-MOF heterojunction structure facilitates rapid mass–charge transfer and exposure of active sites, which significantly enhanced OER activity. Experimental results show that this heterogeneous structure achieves a low overpotential of 333 mV at 10 mA cm–2. The findings provide new insights and directions for the search for highly reactive cobalt-based MOFs for sustainable energy technologies.