Multiple plasmonic effect on photocurrent generation of metal-loaded titanium dioxide composite/dye films on gold grating surface

Abstract

We demonstrate the multiple plasmonic effect on the photocurrent properties of photoanodes containing Ag or Au nanoparticles (NPs) loaded onto titanium dioxide film (Ag-TiO2 or Au-TiO2) on Au grating surfaces. Ag-TiO2 or Au-TiO2 nanocomposite particles are prepared by a flame spray pyrolysis route. The structures and morphologies of the prepared products are characterized by high-resolution transmission electron microscopy. The Ag-TiO2 or Au-TiO2 composite NPs are deposited by spin coating onto the Au grating surfaces. The photoanode electrode is a layered structure of blu-ray disc-recordable grating substrate/Au/Ag (or Au)-TiO 2/dye/electrolyte/indium-tin oxide. The plasmonic effect is induced when Ag or Au NPs are located within the propagating surface plasmon (SP) field on the Au grating surface. The short-circuit photocurrent is increased by exciting the grating-coupled propagating SP on the Au gratings and is further enhanced by positioning the Ag or Au NPs within the grating-coupled SP field. Copyright © 2014 John Wiley & Sons, Ltd.