Synthesis and Characterisation of ZnS and CdS Nanostructures

Abstract

ZnS and CdS materials are known for their wide applications as luminescent ma- terials. Control of dimensions resulting in di erent nanoforms, like: particles, rods, wires, etc. are of great interest with regard to speci c applications of such materials in next generation electronic and photonic devices with low power con- sumption.These II-VI compound semiconductors have been studied for a variety of applications such as optical coatings, photoconductors, optic modulators, electro- optic modulators, at panel displays, electroluminescent devices, sensors, and lasers. These have also been applied in photocatalyst, infrared windows, pigments and non- linear optical devices. Syntheses of ZnS and CdS nanostructures (particles, rods, wires, tubules, owers, cactus-like structures, tetrapods, etc.) through electrochemical template synthesis, solvothermal route and chemical precipitation technique have been presented in this work. The structural, morphological, compositional and optical properties of the synthesized nanoforms have been investigated. The techniques used for the charac- terization of the samples, include: X-ray di raction (XRD), Scanning Electron Mi- croscopy (SEM), Transmission Electron Microscopy (TEM), Electron Di raction X- ray Analysis (EDAX), Fourier Transform Infrared Spectroscopy (FTIR), UV-Visible 1 2 Absorption Spectroscopy, Time-Resolved and Energy-Resolved Photoluminescence (PL) measurements. Transition metal atoms, like: Mn, Cu, Co, Ni, and rare earth materials, like: Tb and Eu have been doped in ZnS nanoparticles. Mn, Eu and Tb metal ions have been doped into CdS nanoforms. The e ect of these dopants on the structure, morphology and optical behavior has been studied in the present work. Moreover, ZnS:Cu and ZnS:Ni nanoparticles have been irradiated by prolonged UV radiation. And ZnS:Co, ZnS:Eu and CdS:Tb nanoforms have been annealed in nitrogen gas atmosphere, and the e ects have been studied. In short, this work presents detailed study of ZnS and CdS nanoforms - doped and undoped - synthesized through di erent bottom-up techniques, as well as their properties. This study is likely to be of use in the eld of optoelectronics, biological sensors, etc.