Collective excitation of plasmonic hot-spots for enhanced hot charge carrier transfer in metal/semiconductor contacts

Abstract

We show how a combination of near- and far-field coupling of the localised surface plasmon resonances in aluminium nanoparticles deposited on TiO₂ films greatly enhances the visible light photocatalytic activity of the semiconductor material. We demonstrate two orders of magnitude enhancement in the rate of decomposition of methylene blue under visible light illumination when the surface of TiO₂ films is decorated with gratings of Al nanoparticle dimers.