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Title: Degradation in photocatalytic activity induced by hydrogen-related defects in nano-LiNbO{sub 3} material

Abstract

As a representative example, nano-LiNbO{sub 3} is prepared by a wet-chemical method in order to enhance its photocatalytic activity through improving the surface area. The samples perform good crystallinity from powder x-ray diffraction and transmission-electron-microscope observations. It is surprising that photocatalytic activity of nano-LiNbO{sub 3} decreases with an increase of its surface area. The presence of hydrogen in the as-prepared LiNbO{sub 3} samples is detected by measuring the OH{sup -} absorption that occurred near 3500 cm{sup -1} in infrared spectra. Though the surface area of the nano-LiNbO{sub 3} samples with good crystallinity increases with a decrease of the sintered temperature, the number of hydrogen-related defects in the samples increases noticeably, thus reducing the photocatalytic activities of the nano-LiNbO{sub 3} samples.

Authors:
; ; ;  [1];  [2]
  1. Ecomaterials and Renewable Energy Research Center, Department of Physics and National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093 (China)
  2. (NIMS), 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047 (Japan)
Publication Date:
OSTI Identifier:
20778639
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 88; Journal Issue: 7; Other Information: DOI: 10.1063/1.2175479; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ABSORPTION; CATALYSIS; CHEMICAL ANALYSIS; CRYSTAL DEFECTS; HYDROGEN; HYDROXIDES; INFRARED SPECTRA; LITHIUM COMPOUNDS; NANOSTRUCTURES; NIOBATES; PHOTOCHEMISTRY; POWDERS; SINTERING; SURFACE AREA; TRANSMISSION ELECTRON MICROSCOPY; X-RAY DIFFRACTION

Citation Formats

Li Zhaosheng, Yu Tao, Zou Zhigang, Ye Jinhua, and Ecomaterials Center, National Institute for Materials Science. Degradation in photocatalytic activity induced by hydrogen-related defects in nano-LiNbO{sub 3} material. United States: N. p., 2006. Web. doi:10.1063/1.2175479.
Li Zhaosheng, Yu Tao, Zou Zhigang, Ye Jinhua, & Ecomaterials Center, National Institute for Materials Science. Degradation in photocatalytic activity induced by hydrogen-related defects in nano-LiNbO{sub 3} material. United States. doi:10.1063/1.2175479.
Li Zhaosheng, Yu Tao, Zou Zhigang, Ye Jinhua, and Ecomaterials Center, National Institute for Materials Science. Mon . "Degradation in photocatalytic activity induced by hydrogen-related defects in nano-LiNbO{sub 3} material". United States. doi:10.1063/1.2175479.
@article{osti_20778639,
title = {Degradation in photocatalytic activity induced by hydrogen-related defects in nano-LiNbO{sub 3} material},
author = {Li Zhaosheng and Yu Tao and Zou Zhigang and Ye Jinhua and Ecomaterials Center, National Institute for Materials Science},
abstractNote = {As a representative example, nano-LiNbO{sub 3} is prepared by a wet-chemical method in order to enhance its photocatalytic activity through improving the surface area. The samples perform good crystallinity from powder x-ray diffraction and transmission-electron-microscope observations. It is surprising that photocatalytic activity of nano-LiNbO{sub 3} decreases with an increase of its surface area. The presence of hydrogen in the as-prepared LiNbO{sub 3} samples is detected by measuring the OH{sup -} absorption that occurred near 3500 cm{sup -1} in infrared spectra. Though the surface area of the nano-LiNbO{sub 3} samples with good crystallinity increases with a decrease of the sintered temperature, the number of hydrogen-related defects in the samples increases noticeably, thus reducing the photocatalytic activities of the nano-LiNbO{sub 3} samples.},
doi = {10.1063/1.2175479},
journal = {Applied Physics Letters},
number = 7,
volume = 88,
place = {United States},
year = {Mon Feb 13 00:00:00 EST 2006},
month = {Mon Feb 13 00:00:00 EST 2006}
}
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