Effect of TiCl4 treatment on photoelectrochemical properties of nanocrystalline CdS particulate films

Cadmium sulfide (CdS) particulate film electrodes were prepared by coating nanosized CdS colloidal sols onto fluorine-doped tin oxide conducting glass, and treated with titanium tetrachloride aqueous solution. The variation of photoelectrochemical properties of these electrodes according to the surface treatment was investigated with respect to photocurrent and surface morphology. Porous films composed of coarsely interconnected CdS particles before treatment became more compact and stable after treatment. It was also found that the TiO2 component was formed homogeneously throughout the entire film. This etching and TiO2 effect brought about densification of the films, a decrease of film surface area, and an enhancement of the photocurrent. Especially, the stabilities of the electrodes measured by chronoamperometry were remarkably improved by the treatment, suggesting the effectiveness of this approach. (C) 2001 The Electrochemical Society.