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 materialshave garneredattention as promising candidates for electrocatalytic oxygen evolutionreactions (OER). However, it remains a challenge to understandingthe structure-activity relationship of these materials at thesingle-particle level due to the limited resolution of characterizations.Here, we present an efficient approach that combines a single-particle-at-the-tiptechnique with scanning electrochemical cell microscopy to reveala relationship between the microstructure and electrochemical activityfor sheet-like nickel-based MOF particles. We find a negative correlationbetween the sheet thickness and the OER activity based on statisticaldata at the single-particle level. The origin of the enhanced OERactivity can be rationalized by the larger fraction of the (001) facet.Simultaneously, the derivation process of catalysts is documentedto ensure the accuracy of structural information. This study enablesa simple single-entity electrochemical strategy to understand themicrostructure-activity relationship of MOF-based catalysts(MOF-C) and offers new insights into the design of high-performanceMOF-C.