Simple CVD routes towards infiltration of mesoporous TiO2

There is considerable interest in developing simple, single-step chemical procedures for controlled infiltration of mesoporous materials in order to create novel structures with practical applications. In this paper, we demonstrate the use of low-pressure metal-organic (MO)CVD and aerosol assisted (AA)CVD methods for infiltration and growth of compound semiconductors (CdS and CuInS2) within mesoporous TiO2 thin films using single-source dithiocarbamate precursors. The relative rates of surface reaction and diffusion of precursors can be controlled through simple modification of our existing single-step CVD processes. Films have been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM). energy dispersive X-ray (EDX), and electronic spectroscopy. Promising transient absorption data have been obtained for mesostructured CuInS2/ TIO2 films, which suggest the AACVD-grown ternary has desirable properties for employment as a solar sensitizer in solid-state inorganic photovoltaic cells. The simplicity of the approach may also find practical applications in the production of inverse opals for photonic crystals and thin films.