Realization of structural and optical properties of CdZnO composite coated films for photovoltaic cell applications.

CdZnO composite coated films were deposited on glass substrate by screen printing method at the sintering temperature of 450 °C and 550 °C. The morphological and structural details of composite films were characterized by Scanning Electron microscope (SEM), Powder X-Ray Diffraction (XRD) and Fourier Transform Infrared (FTIR) techniques. Similarly, optical properties were analyzed by UV–vis and Photoluminescence (PL) spectroscopy. XRD patterns revealed increase in crystallite size with increasing sintering temperature. SEM images clearly show agglomeration and increase in the grain size of the nanoparticles in high temperature sintered film. Similarly, FTIR spectra exhibit a slight shift in peak positions and increase in intensity of peaks with increase in sintering temperature. The optical absorption measurements have been used to evaluate the values of refractive index, extinction coefficients of these direct- energy band gap semiconductor films with energy band gaps distributed in the range of ∼2.81 eV at 450 °C and ∼2.70 eV at 550 °C. The imaginary and real parts of dielectric constants are also calculated, while PL spectra showed band emission shifting towards the higher side (red shift) with increase in sintering temperature. These studies revealed that on increasing sintering temperature the crystallinity of the film improves with reduction in lattice deformations in such composite films. [ABSTRACT FROM AUTHOR]