One-pot solvothermal synthesis and characterization of CdS nanotubes decorated with graphene for solar cell applications

Exfoliated graphene oxide was prepared and used to synthesize graphene-CdS ( G-CdS) nanocomposites with different concentrations. CdS and G-CdS nanocomposites have successfully been synthesized via solvothermal method. The prepared materials were characterized by Fourier transform infrared, X-ray diffraction and high resolution transmission electron microscope techniques. CdS was found to grow as nanotubes with wurtzite crystal structure. CdS and G-CdS films were prepared by spin coating technique onto optical flat quartz and InP substrates. The optical properties were investigated by spectrophotometric measurements of the transmittance and reflectance over the spectral range 200-2500 nm. The optical band gap of the films was found to increase with increasing graphene content. The solar cells in the configuration of In/G-CdS/p-InP/Au: Zn with different graphene content were fabricated and compared with that fabricated with pristine CdS. The current-voltage characteristics of the devices were measured in dark and under illumination in which the basic diode parameters and photovoltaic parameters were estimated. The results demonstrate that the decoration of CdS with graphene is a promising simple approach to improve the electrical conversion efficiency of solar cells. (C) 2016 Elsevier B. V. All rights reserved.