An efficient visible-light active photocatalyst CuAlGaO4 for solar hydrogen production

Herein, for the first time, CuAlGaO4 is demonstrated as an efficient visible-light-active (band-gap of 1.87 eV, lambda >= 420 nm) photocatalyst for solar H-2 production. The CuAlGaO4 prepared by solid-state method is capable of producing 3214 mu mol of H-2 per hour from H2S photodecomposition under visible-light irradiation with quantum yield of 10.8% at 550 nm. Loading with 1 wt.% NiO enhances the rate of H-2 generation of the photocatalyst to 3616 mu molh(-1) with quantum yield of 12.7% at 550 nm. The CuAlGaO4 exhibits a spinel structure with particle size varying from a few nanometers to a few micrometers. The regenerated catalysts validate the stability and the reusability. (C) 2010 Elsevier B.V. All rights reserved.