Identifying Representative Structural Model in Atomically Dispersed Catalysts

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.