Photosensitization of nanocrystalline TiO2 film electrode with cadmium sulphoselenide

Abstract

Nanocrystalline titanium dioxide (TiO2) thin films composed of densely packed nanometer-sized grains have been successfully deposited onto an indium-doped-tin oxide (ITO) substrate. Then cadmium sulphoselenide (CdSSe) thin film was deposited onto pre-deposited TiO2 to form a TiO2/CdSSe film, at low temperature using a simple and inexpensive chemical method. The X-ray diffraction, selected area electron diffraction, scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX) and water contact angle techniques were used for film characterization. Purely rutile phase of TiO2 with super-hydrophilic and densely packed nanometer-sized spherical grains of approximate diameter 30-40 (+/- 2) nm was observed. The increase in optical absorption was observed after CdSSe film deposition. Nest like surface morphology of CdSSe on TiO2 surface results in air trapping in the crevices which prevents water from adhering to the film with increase in water contact angle. Photosensitization of TiO2 with CdSSe was confirmed with light illumination intensity of 80 mW/cm(2).