Optimized CdO:TiO2 nanocomposites for heterojunction solar cell applications

Abstract

In the present work, different volume compositions of CdO:TiO2 were synthesized and thin films were deposited on glass substrate by spin coating technique and subsequently composition of CdO:TiO2 was optimized and grown on p-Si for solar cell application. The XRD results exhibit that by increasing the volume fraction of TiO2 in CdO, the Ti+4 ions occupied in the interstitial positions or creates Cd+2 ion vacancies in the lattice of CdO causes increment in the peak intensity of cubic structure of CdO. The continuous change in the surface morphology from nanograins to crakes were investigated by FE-SEM. UV–Vis spectrophotometer was used for recording the transmittance in the range of wavelength 300 nm–800 nm and optical band gap was found decreased from 2.38 eV to 1.70 eV by increasing the TiO2 volume ratio in CdO. The minimum value of resistivity was obtained 2 × 10−2 Ω cm for optimized thin film. The current density voltage (J-V) curve was used for estimating the fill factor (0.53) and conversion efficiency (3.23%) of optimized device under the illumination of 100 mW/cm2. The overall study reveals that nanocomposites of CdO:TiO2 successfully reduced the toxicity of CdO and enhanced the conductivity by adding TiO2.