Comparative Study of EPR and Optical Properties of CdS, TiO2 and CdS-TiO2 Nanocomposite
An economical chemical route is used to synthesize a titanium oxide-based nanocomposite (NC) which has properties that may help to develop photocatalysts with improved efficiency in the visible region of solar light. Investigation of opto-electronic properties has been carried out for a CdS, TiO2 and CdS-TiO2 NC at room temperature. Structural properties of the CdS and TiO2 nanoparticles and the CdS-TiO2 NC were investigated using x-ray diffraction and transmission electron microscopy techniques. How incorporation of CdS nanoparticles affects the structural properties of pure TiO2 was also studied. Change in optical behavior was compared using UV–visible and photoluminescence spectra, and the presence of residual functional groups were indicated by Fourier-transform infrared analysis of the samples. The measurement of band levels was carried out by cyclic voltammetry (CV) and the band gap estimated from UV–visible was compared to that obtained by CV. The electron paramagnetic resonance technique was used for the investigation of the electronic properties of the samples.