Intrinsic and external active sites of single-atom catalysts
Xue Yao,
Ethan Halpren,
Ye Zhou Liu,
Chung Hsuan Shan,
Zhi Wen Chen,
Li Xin Chen,
Chandra Veer Singh
Affiliations
Xue Yao
Department of Materials Science and Engineering, University of Toronto, Toronto, ON M5S 3E4, Canada
Ethan Halpren
Department of Materials Science and Engineering, University of Toronto, Toronto, ON M5S 3E4, Canada
Ye Zhou Liu
Department of Materials Science and Engineering, University of Toronto, Toronto, ON M5S 3E4, Canada
Chung Hsuan Shan
Department of Materials Science and Engineering, University of Toronto, Toronto, ON M5S 3E4, Canada
Zhi Wen Chen
Department of Materials Science and Engineering, University of Toronto, Toronto, ON M5S 3E4, Canada
Li Xin Chen
Department of Materials Science and Engineering, University of Toronto, Toronto, ON M5S 3E4, Canada; Corresponding author
Chandra Veer Singh
Department of Materials Science and Engineering, University of Toronto, Toronto, ON M5S 3E4, Canada; Department of Mechanical and Industrial Engineering, University of Toronto, Toronto, ON M5S 3G8, Canada; Corresponding author
Summary: Active components with suitable supports are the common paradigm for industrial catalysis, and the catalytic activity usually increases with minimizing the active component size, generating a new frontier in catalysis, single-atom catalysts (SACs). However, further improvement of SACs activity is limited by the relatively low loading of single atoms (SAs, which are heteroatoms for most SACs, i.e., external active sites) because of the highly favorable aggregation of single heteroatoms during preparation. Research interest should be shifted to investigate SACs with intrinsic SAs, which could circumvent the aggregation of external SAs and consequently increase the SAs loading while maintaining them individual to further improve the activity. In this review, SACs with external or intrinsic SAs are discussed and, at last, the perspectives and challenges for obtaining high-loading SACs with intrinsic SAs are outlined.
