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Title: Quantum-size effect on the electronic and optical properties of hybrid TiO{sub 2}/Au clusters

Abstract

Although TiO{sub 2}/Au nanosystems exhibit high photocatalytic activities under solar radiation in the experiment, the quantum-size effect of TiO{sub 2} on the growth, electronic properties, and reactivity of Au clusters remains elusive. Using (time dependent) density functional theory, it is found that Au atoms attach to low-coordinated Ti and O atoms and serve as seeds for the growth of Au clusters, and the electronic (optical) properties of hybrid Au-TiO{sub 2} nano-clusters depend strongly upon the type of supported Au clusters. Interestingly, decorating TiO{sub 2} nano-particles with even-numbered Au clusters (Au{sub 8} or Au{sub 10}) can enhance the photocatalytic activity by: (i) spatially separating electron and hole states and (ii) balancing redox strength and visible light absorption. Furthermore, the interactions between the Au-TiO{sub 2} clusters and a single water molecule have been studied. It will open up new avenues for exploring controlled photocatalysts in semiconductor-based quantum-confined systems.

Authors:
; ;  [1];  [2];  [3]
  1. College of Electronic Science and Engineering, Nanjing University of Posts and Telecommunications, Nanjing 210046 (China)
  2. Nanjing National Laboratory of Microstructures, Nanjing University, Nanjing 210093 (China)
  3. Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031 (China)
Publication Date:
OSTI Identifier:
22419991
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 141; Journal Issue: 5; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ABSORPTION; DENSITY FUNCTIONAL METHOD; ELECTRONS; HYBRIDIZATION; INTERACTIONS; MOLECULES; OPTICAL PROPERTIES; PARTICLES; PHOTOCATALYSIS; SEMICONDUCTOR MATERIALS; SOLAR RADIATION; TIME DEPENDENCE; TITANIUM OXIDES

Citation Formats

Liu, Chun-Sheng, E-mail: csliu@njupt.edu.cn, E-mail: yexiaojuan1980@gmail.com, Wang, Xiangfu, Yan, Xiaohong, Ye, Xiaojuan, E-mail: csliu@njupt.edu.cn, E-mail: yexiaojuan1980@gmail.com, and Zeng, Zhi. Quantum-size effect on the electronic and optical properties of hybrid TiO{sub 2}/Au clusters. United States: N. p., 2014. Web. doi:10.1063/1.4891241.
Liu, Chun-Sheng, E-mail: csliu@njupt.edu.cn, E-mail: yexiaojuan1980@gmail.com, Wang, Xiangfu, Yan, Xiaohong, Ye, Xiaojuan, E-mail: csliu@njupt.edu.cn, E-mail: yexiaojuan1980@gmail.com, & Zeng, Zhi. Quantum-size effect on the electronic and optical properties of hybrid TiO{sub 2}/Au clusters. United States. doi:10.1063/1.4891241.
Liu, Chun-Sheng, E-mail: csliu@njupt.edu.cn, E-mail: yexiaojuan1980@gmail.com, Wang, Xiangfu, Yan, Xiaohong, Ye, Xiaojuan, E-mail: csliu@njupt.edu.cn, E-mail: yexiaojuan1980@gmail.com, and Zeng, Zhi. Thu . "Quantum-size effect on the electronic and optical properties of hybrid TiO{sub 2}/Au clusters". United States. doi:10.1063/1.4891241.
@article{osti_22419991,
title = {Quantum-size effect on the electronic and optical properties of hybrid TiO{sub 2}/Au clusters},
author = {Liu, Chun-Sheng, E-mail: csliu@njupt.edu.cn, E-mail: yexiaojuan1980@gmail.com and Wang, Xiangfu and Yan, Xiaohong and Ye, Xiaojuan, E-mail: csliu@njupt.edu.cn, E-mail: yexiaojuan1980@gmail.com and Zeng, Zhi},
abstractNote = {Although TiO{sub 2}/Au nanosystems exhibit high photocatalytic activities under solar radiation in the experiment, the quantum-size effect of TiO{sub 2} on the growth, electronic properties, and reactivity of Au clusters remains elusive. Using (time dependent) density functional theory, it is found that Au atoms attach to low-coordinated Ti and O atoms and serve as seeds for the growth of Au clusters, and the electronic (optical) properties of hybrid Au-TiO{sub 2} nano-clusters depend strongly upon the type of supported Au clusters. Interestingly, decorating TiO{sub 2} nano-particles with even-numbered Au clusters (Au{sub 8} or Au{sub 10}) can enhance the photocatalytic activity by: (i) spatially separating electron and hole states and (ii) balancing redox strength and visible light absorption. Furthermore, the interactions between the Au-TiO{sub 2} clusters and a single water molecule have been studied. It will open up new avenues for exploring controlled photocatalysts in semiconductor-based quantum-confined systems.},
doi = {10.1063/1.4891241},
journal = {Journal of Chemical Physics},
number = 5,
volume = 141,
place = {United States},
year = {Thu Aug 07 00:00:00 EDT 2014},
month = {Thu Aug 07 00:00:00 EDT 2014}
}
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