Applied Surface Science, Vol.425, 576-584, 2017
Water-driven stabilization of cadmium sulphide nanoparticles
Water driven stabilization of cadmium sulphide (CdS) nanoparticles, synthesized through a novel and facile electro-explosion of wire (EEW) technique, is reported by us. The transformation of prepared material was visually evident; as greenish black colour of the colloidal as well as the powder particles, obtained just after the synthesis, changed to orange colour after one month. Cubic Hawleyite phase CdS nanoparticles with 2.3-13.4 nm average crystallite size were ascertained by XRD analysis. HRTEM and AFM analysis collectively confirmed the formation of stable CdS nanoparticles. The crucial S-H vibrational mode, a signature interaction of CdS nanoparticles with surrounding water molecules, was revealed by FTIR analysis. The composition of prepared nanoparticles was accessed through XPS analysis. Not only structural but optical properties of nanoparticles also altered due to aging of nanoparticles. Enhanced band gap of CdS nanoparticles and gradual prominence of absorption energy with aging were demonstrated through UV-vis analysis. Complementary to this, PL spectroscopic analysis revealed the photophysics of CdS nanoparticles by providing details of radiative recombination channels. Thus, intricacies of CdS nanoparticles stabilization in aqueous environment were unravelled on the basis of variations in crystallinity, local chemical environment, alterations in electronic structure and optical processes occurring therein. (C) 2017 Elsevier B.V. All rights reserved.
Keywords:Nanoscale materials and structures: fabrication and characterization;Structural transitions in nanoscale materials;X-ray diffraction;Photoemission and photoelectron spectra;Optical properties of low-dimensional, mesoscopic, and nanoscale and structures