1. Spatial Charge Separation in Asymmetric Structureof Au Nanoparticle on TiO2Nanotube by Light-Induced SurfacePotential Imaging.
- Author
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Yoo, Hyunjun, Bae, Changdeuck, Yang, Yunjeong, Lee, Seonhee, Kim, Myungjun, Kim, Hyunchul, Kim, Yunseok, and Shin, Hyunjung
- Subjects
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SILVER nanoparticles , *TITANIUM oxides , *SURFACE potential , *CHARGE transfer , *ENERGY conversion , *NANOSTRUCTURED materials - Abstract
Bothenhancing the excitons’ lifetime and ingeniously controllingthe spatial charge transfer are the key to the realization of efficientlyphotocatalytic and artificially photosynthetic devices. Nanostructuredmetal/metal-oxide interfaces often exhibit improved energy conversionefficiency. Understanding the surface potential changes of nano-objectsunder light illumination is crucial in photoelectrochemical cells.Under ultraviolet (UV) illumination, here, we directly observed thecharge separation phenomena at the Au-nanoparticle/TiO2-nanotube interfaces by using Kelvin probe force microscopy. Thesurface potential maps of TiO2nanotubes with and withoutAu nanoparticles were compared on the effect of different substrates.We observed that in a steady state, approximately 0.3 electron perAu particle of about 4 nm in diameter is effectively charged and consequentlyscreens the surface potential of the underlying TiO2nanotubes.Our observations should help design improved photoelectrochemicaldevices for energy conversion applications. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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