Structure Sensitivity of Au-TiO2 Strong Metal-Support Interactions

Yunshang Zhang; Jin-Xun Liu; Kun Qian; Aiping Jia; Dan Li; Lei Shi; Jun Hu; Junfa Zhu; Weixin Huang

doi:10.1002/anie.202101928

Structure Sensitivity of Au-TiO₂ Strong Metal-Support Interactions

Angew Chem Int Ed Engl. 2021 May 17;60(21):12074-12081. doi: 10.1002/anie.202101928. Epub 2021 Apr 16.

Authors

Yunshang Zhang^{1

2}, Jin-Xun Liu^{1

2}, Kun Qian^{1

2}, Aiping Jia^{2

3}, Dan Li^{1

2}, Lei Shi¹, Jun Hu⁴, Junfa Zhu⁴, Weixin Huang^{1

2

5}

Affiliations

¹ Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, 230026, P. R. China.
² Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes and Department of Chemical Physics, University of Science and Technology of China, Hefei, 230026, P. R. China.
³ Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, Institute of Physical Chemistry, Zhejiang Normal University, Jinhua, 321004, China.
⁴ National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui, 230029, China.
⁵ Dalian National Laboratory for Clean Energy, Dalian, 116023, China.

PMID: 33709509
DOI: 10.1002/anie.202101928

Abstract

Strong metal-support interactions (SMSI) is an important concept in heterogeneous catalysis. Herein, we demonstrate that the Au-TiO₂ SMSI of Au/TiO₂ catalysts sensitively depends on both Au nanoparticle (NP) sizes and TiO₂ facets. Au NPs of ca. 5 nm are more facile undergo Au-TiO₂ SMSI than those of ca. 2 nm, while TiO₂ {001} and {100} facets are more facile than TiO₂ {101} facets. The resulting capsulating TiO_2-x overlayers on Au NPs exhibit an average oxidation state between +3 and +4 and a Au-to-TiO_2-x charge transfer, which, combined with calculations, determines the Ti:O ratio as ca. 6:11. Both TiO_2-x overlayers and TiO_2-x -Au interface exhibit easier lattice oxygen activation and higher intrinsic activity in catalyzing low-temperature CO oxidation than the starting Au-TiO₂ interface. These results advance fundamental understanding of SMSI and demonstrate engineering of metal NP size and oxide facet as an effective strategy to tune the SMSI for efficient catalysis.

Keywords: facet effect; interfacial catalysis; low-temperature CO oxidation; metal-support interactions; size effect.

Abstract

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