Efficient visible-light photocatalytic water spilitting by minute amounts of golds supported on nanoparticulate CeO2 obtaines by a biopolymer templating method

Abstract

When irradiated with visible light (¿ > 400 nm) 1wt%gold-supported ceria nanoparticles generate oxygen from water (10.5 ¿mol 3 h 1)moreefficiently than the standardWO3 (1.7 ¿mol 3 h 1) even under UV irradiation (9.5 ¿mol 3 h 1). This remarkable photocatalytic activity arises from a novel preparation method to reduce the particle size of ceria (5 nm) by means of electrostatic binding of Ce4¿ to alginate gel, subsequent supercritical CO2 drying, and calcination. The low loading of Au is crucial for the observed high catalytic activity.