Resolving the puzzle of single-atom silver dispersion on nanosized γ-Al₂O₃ surface for high catalytic performance

Authors

Fei Wang, Chinese Academy of Sciences, Beijing
Jinzhu Ma, Chinese Academy of Sciences, Beijing
Shaohui Xin, University of Chinese Academy of Sciences, Beijing
Qiang Wang, Wuhan Institute of Physics and Mathematics
Jun Xu, Wuhan Institute of Physics and Mathematics
Changbin Zhang, Chinese Academy of SciencesFollow
Hong He, Chinese Academy of Sciences, Beijing
Xiao Cheng Zeng, University of Nebraska - LincolnFollow

ORCID IDs

Fei Wang http://orcid.org/0000-0002-4364-9956

Qiang Wang http://orcid.org/0000-0001-7741-3733

Xiao Cheng Zeng http://orcid.org/0000-0003-4672-8585

Date of this Version

2020

Citation

NATURE COMMUNICATIONS (2020) 11:529

doi:10.1038/s41467-019-13937-1

Comments

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License

Abstract

Ag/γ-Al₂O₃ is widely used for catalyzing various reactions, and its performance depends on the valence state, morphology and dispersion of Ag species. However, detailed anchoring mechanism of Ag species on γ-Al₂O₃ remains largely unknown. Herein, we reveal that the terminal hydroxyls on γ-Al₂O₃ are responsible for anchoring Ag species. The abundant terminal hydroxyls existed on nanosized γ-Al₂O₃ can lead to single-atom silver dispersion, thereby resulting in markedly enhanced performance than the Ag cluster on microsized γ-Al₂O₃. Density-functional-theory calculations confirm that Ag atom is mainly anchored by the terminal hydroxyls on (100) surface, forming a staple-like local structure with each Ag atom bonded with two or three terminal hydroxyls. Our finding resolves the puzzle on why the single-atom silver dispersion can be spontaneously achieved only on nanosized γ-Al₂O₃, but not on microsized γ-Al₂O₃. The obtained insight into the Ag species dispersion will benefit future design of more efficient supported Ag catalysts.