The Microstructure–Activity Relationship of Metal–Organic Framework-Based Electrocatalysts for the Oxygen Evolution Reaction at the Single-Particle Level

Metal–organic framework (MOF)-based materials have garnered attention as promising candidates for electrocatalytic oxygen evolution reactions (OER). However, it remains a challenge to understanding the structure–activity relationship of these materials at the single-particle level due to the limited resolution of characterizations. Here, we present an efficient approach that combines a single-particle-at-the-tip technique with scanning electrochemical cell microscopy to reveal a relationship between the microstructure and electrochemical activity for sheet-like nickel-based MOF particles. We find a negative correlation between the sheet thickness and the OER activity based on statistical data at the single-particle level. The origin of the enhanced OER activity can be rationalized by the larger fraction of the (001) facet. Simultaneously, the derivation process of catalysts is documented to ensure the accuracy of structural information. This study enables a simple single-entity electrochemical strategy to understand the microstructure–activity relationship of MOF-based catalysts (MOF-C) and offers new insights into the design of high-performance MOF-C.