Advances in the understanding of the structure–performance relationships of 2D material catalysts based on electron microscopy

Abstract

Two-dimensional (2D) materials have gradually emerged as novel electrocatalysts in energy conversion applications due to their unique atomic configuration and electronic characteristics. However, the ultrathin layered structure and diverse atomic structure seriously hinder macroscopic characterization in studying their catalytic mechanism. Advanced electron microscopy technologies provide opportunities to directly explore the structure–performance relationships of 2D catalysts at the atomic level. This review covers the recent progress of electron microscopy techniques in understanding the relationship between the surface structure and catalytic performance of 2D electrocatalysts. The principles of various electron microscopy techniques and their functionalities in characterizing the surface structure, coordination environment, defects and disorderings that affect the catalytic activity of ultrathin two-dimensional materials are discussed in detail, and provide strong support for revealing the working mechanisms of 2D catalytic materials. Finally, the main challenges and future directions in exploring 2D catalytic materials with electron microscopy are presented.