Identifying Representative Structural Model in Atomically Dispersed Catalysts
Guolei Cai, Haifeng Lv, Yifan Li, Guikai Zhang, Jing Zhang, Xianghua Kong, Xiaojun Wu, Song Wan Jin, Hengxing Ji
Abstract
Atomically dispersed catalysts (ADCs) embedded within carbon substrates are gaining considerable attention for their high metal atom utilization and exceptional catalytic activity. The coordination structure of the active catalytic center is crucial to catalytic performance; however, accurately characterizing these structures remains challenging due to the inherent structural diversity in real-world ADCs and the difficulty of identifying the light elements (e.g., C and N) surrounding central metal atoms. Herein, we propose a protocol to interpret the X-ray absorption spectroscopy, thereby identifying the most probable representative structures of ADCs. Our method integrates average coordination numbers, oxidation states of central metal atoms, and the specific light elements bonded to these metal atoms. This protocol is applicable to single-, dual-, and trimetal atom catalysts, offering a more rational method for structural assignment. By addressing key methodological limitations in current structural assignments for ADCs, our approach improves the reliability of active site identification and provides a foundation for more accurate structure-activity relationship studies in catalytic systems.