Effects of plasmon excitation on photocatalytic activity of Ag/TiO2 and Au/TiO2 nanocomposites
Journal article, 2013

Model nanocomposite photocatalysts consisting of undoped TiO2 films with optically active Ag or Au nanoparticles (NPs) were designed, fabricated, and examined to address the role of plasmon excitations in their performance. Different composition configurations were tested in which the NPs were either facing the reaction environment or not, and in direct contact or not with TiO2. We found, as measured for the reactions of methanol and ethylene oxidation in two different photoreactors, that composites always show enhanced activity (up to x 100 for some configurations) compared to bare TiO2. We deduced from in situ localized surface plasmon resonance spectroscopy measurements that the interfacial charge transfer from TiO2 to NPs plays a major role in the activity enhancement for composite configurations where particles are in direct contact with TiO2. Plasmonic near- and far-field effects were only observed when the plasmon resonance energy overlaps with the bandgap energy of undoped TiO2. (C) 2013 Elsevier Inc. All rights reserved.

Nanocomposites

CHARGE SEPARATION

Metal nanoparticles

UV

Photocatalysis

GOLD NANOPARTICLES

VISIBLE-LIGHT

TIO2

SIZE

SURFACE-PLASMONS

WATER

ELECTRON-TRANSFER

Mechanisms

Plasmonics

NANOPARTICLES

TiO2

METAL NANOPARTICLES

Author

Raja Sellappan

Chalmers, Applied Physics, Chemical Physics

M. G. Nielsen

Technical University of Denmark (DTU)

Fernando Gonzalez-Posada

Chalmers, Applied Physics, Chemical Physics

P. C. K. Vesborg

Technical University of Denmark (DTU)

I. Chorkendorff

Technical University of Denmark (DTU)

Dinko Chakarov

Chalmers, Applied Physics, Chemical Physics

Journal of Catalysis

0021-9517 (ISSN) 1090-2694 (eISSN)

Vol. 307 214-221

Subject Categories

Physical Chemistry

DOI

10.1016/j.jcat.2013.07.024

More information

Latest update

2/28/2018