Au nanoparticle sensitized ZnO nanopencil arrays for photoelectrochemical water splitting

Abstract

This paper describes the synthesis of Au nanoparticle sensitized ZnO nanopencil arrays on F-doped SnO₂ substrates by an aqueous chemical growth and subsequent photoreduction method. The Au–ZnO nanopencil arrays yield a photocurrent of ∼1.5 mA cm⁻² at 1 V versus Ag/AgCl. The enhanced photocurrent is attributed to the surface plasmon resonance effect of Au nanoparticles and the prolonged lifetime of the photo-generated electron–hole pairs. The improved stability of ZnO is due to the plasmon resonance energy transfer process enabled by the Au nanoparticles, which enhances the electric field intensity in a small, well-defined location of the ZnO semiconductor.