Structural, optical and electrical properties of ZnO-ZnS nanocomposites prepared by simple hydrothermal method

ZnO-ZnS nanocomposites with different molar ratio 25:75, 50:50 and 75:25 percentages were prepared by the simple hydrothermal method. The techniques used for the characterization of samples were X-ray diffractometry (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX) analysis, UV-visible diffuse reflectance spectrometry (DRS), Fourier transformed infrared (FT-IR) spectroscopy, dielectric and photoconductivity measurements. XRD patterns confirmed the crystalline nature of ZnO-ZnS nanocomposites. The calculated average crystallite size using Debye Scherrer's equation is in the range of 48-45 nm and 24-21 nm for ZnO and ZnS compound respectively. SEM images showed spherical morphology with agglomerated nanoparticles. The energy dispersive X-ray technique is opted for elemental mapping of ZnO-ZnS nanocomposite. Optical studies of UV-DRS reveal the band gap to be 2.07-2.11 eV. The FT-IR spectra confirmed stretching vibrations of ZnO and ZnS respectively. Dielectric properties like dielectric loss, dielectric constant and AC conductivity were studied. The photoconductivity measurement exhibits good photo response behavior in the nanocomposite materials.