(Au-Ag)-Au double shell nanoparticles loaded on rutile TiO sub(2) for photocatalytic decomposition of 2-propanol under visible light irradiation

We synthesized (core-shell)-shell ((Au-Ag)-Au) nanoparticles (NPs) by a multistep citrate reduction method for utilization as photosensitizers of TiO sub(2). The (Au-Ag)-Au NPs exhibited strong photoabsorption in visible light response due to LSPR excitation of the Ag shell, and its LSPR characteris...

Full description

Saved in:
Bibliographic Details
Published in:Applied catalysis. B, Environmental Environmental, 2016-01, Vol.180, p.255-262
Main Authors: Kamimuraa, Sunao, Miyazakia, Takeshi, Zhangc, Ming, Lic, Yuqing, Tsubotaa, Toshiki, Ohnoa, Teruhisa
Format: Article
Language:English
Subjects:
Acetone
Evolution
Excitation
Light irradiation
Nanoparticles
Photocatalysis
Rutile
Titanium dioxide
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We synthesized (core-shell)-shell ((Au-Ag)-Au) nanoparticles (NPs) by a multistep citrate reduction method for utilization as photosensitizers of TiO sub(2). The (Au-Ag)-Au NPs exhibited strong photoabsorption in visible light response due to LSPR excitation of the Ag shell, and its LSPR characteristics were stable under visible light irradiation for a long time because oxidation of the Ag shell was prevented by the outermost Au shell. Furthermore, we successfully loaded (Au-Ag)-Au NPs on rutile TiO sub(2) by an impregnation method. (Au-Ag)-Au/TiO sub(2) could oxidize 2-propanol into acetone and CO sub(2) under visible light irradiation ( lambda > 440 nm), and its acetone evolution rate was approximately 15-times higher than that of Au/TiO sub(2). From a comparison of action spectra for acetone evolution and the Kubelka-Munk function, it was confirmed that photocatalytic activity of (Au-Ag)-Au/TiO sub(2) was induced by photoabsorption based on LSPR excitation of the Ag shell. In addition, photoelectrochemical measurements revealed electron injection from LSPR-excited (Au-Ag)-Au NPs into TiO sub(2) under visible light irradiation. We proposed the photocatalytic reaction process of (Au-Ag)-Au/TiO sub(2) in conjunction with optical, structural and photoelectrochemical properties.
ISSN:0926-3373
DOI:10.1016/j.apcatb.2015.06.037