Au Nanoparticle-Enhanced Photocatalysis: Beyond Plasmonic Effect

Plasmonic metal nanostructures have strong, tunable absorption and scattering band. Coupling semiconductors with metal nanoparticles can apparently increase their photocatalytic activity. Besides the plasmonic effect, gold nanoparticles may bring other beneficial effects in the metal-semiconductor composite photocatalyst system. Herein we show that Au nanoparticles sandwiched between the quantum dots (QDs) and the TiO₂ nanorod array photoelectrode can act as an electron relay to facilitate the charge transfer. In another case, Au nanoparticles are deposited on the surface of semiconductor photoelectrode, which can also facilitate the charge transfer. A better understanding of different effects of gold nanoparticles will help develop effective metal-semiconductor device for solar fuel generation.