Chinese Journal of Catalysis ›› 2017, Vol. 38 ›› Issue (9): 1558-1565.DOI: 10.1016/S1872-2067(17)62829-8

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Investigation of water adsorption and dissociation on Au1/CeO2 single-atom catalysts using density functional theory

Yan Tanga, Yang-Gang Wanga, Jin-Xia Lianga,b, Jun Lia   

  1. a Department of Chemistry and Key Laboratory of Organic Optoelectronics & Molecular Engineering of Ministry of Education, Tsinghua University, Beijing 100084, China;
    b Guizhou Provincial Key Laboratory of Computational Nano‐Material Science, Guizhou Normal College, Guiyang 550018, China
  • Received:2017-03-10 Revised:2017-04-01 Online:2017-09-18 Published:2017-09-06
  • Contact: 10.1016/S1872-2067(17)62829-8
  • Supported by:

    This work was supported by the National Natural Science Foundation of China (21590792, 91645203 and 21521091).

Abstract:

We examined the water adsorption and dissociation on ceria surfaces as well as ceria-supported Au single-atom catalysts using density functional theory calculations. Molecular and dissociative water were observed to coexist on clean CeO2 and reduced Au1/CeO2-x surfaces because of the small dif-ference in adsorption energies, whereas the presence of dissociative water was highly favorable on reduced CeO2-xand clean Au1/CeO2 surfaces. Positively charged Au single atoms on the ceria surface not only provided activation sites for water adsorption but also facilitated water dissociation by weakening the intramolecular O-H bonds. In contrast, negatively charged Au single atoms were not reactive for water adsorption because of the saturation of Au 5d and 6s electron shells. This work provides a fundamental understanding of the interaction between water and single-atom Au cata-lysts.

Key words: Single-atom catalyst, Au single atom, Ceria, H2O dissociation