Temperature dependent structural, optical and electrical properties of CuS nanorods in aloe vera matrix

Abstract

Coper sulphide nanorods were synthesized in an aqueous solution by a simple chemical route using copper acetate monohydrate and thiourea as reactants in different ambient temperatures with aloe vera as a green capping material. The as prepared nanorods were characterized with XRD, HRTEM, UV–Vis. absorption and PL spectroscopy, FTIR and EDAX analysis. The electrical conductivity of the electrolytic ionic CuS solution was measured by a standard conductivity cell. The XRD confirmed the polycrystalline hexagonal structure of CuS nanorods. The HRTEM exhibited well defined nanorods distributed in large areas. The UV–Vis. absorption and the PL spectra showed a systematic blue shift of absorption and UV-blue emission confirming quantum confinement effect in the synthesized nanorods. Optical band gap as estimated from Tauc-plot increased from 3.0eV to 3.8eV with increase of temperature. The particle sizes calculated from XRD results by Debye–Scherrer and W–H plots are in well agreement with those obtained from HRTEM results. Aloe vera acted as a good green capping material in quantum confinement of nanorods. FTIR spectra exhibited Cu–S stretching peak at 620 cm−1 which is characteristic of CuS. Electrical properties of ionic solution of CuS indicated good semiconducting nature of CuS. Ionic parameters are estimated and correlated to molar concentration. The EDAX analysis confirmed atomic % of copper and sulphur in CuS. The synthesized material may be used in fabrication of an optoelectronic device in UV-blue region.