Structural and Electrical Studies on ZnS Quantum Dots Using PEG as Capping Agent

Abstract

AbstractZinc sulfide (ZnS) nanoparticles are produced in this study utilizing a simple wet‐chemical precipitation procedure using polyethylene glycol (PEG) as a capping agent. To analyze the structural, morphological, electrical, and electronic properties of the material, the ZnS nano powder is studied using X‐ray diffraction (XRD), scanning electron microscopy (SEM), FTIR, UV–visible absorption spectroscopy, and impedance spectroscopy techniques. The XRD patterns confirm the formation of the cubic phase in as‐prepared ZnS samples, whereas SEM and AFM images show the formation of prismatic and spherical morphology of nano crystallites, confirming the XRD results. FTIR spectra confirm formation of ZnS stoichiometric compound with a partial shifting of vibration bands in the presence of PEG in precursor solution. Optical band gap spectra show a blue shift of band gap with decrease in particle size. The controlled growth kinetics in the presence of PEG the ZnS synthesized nanoparticles show a better quantum confinement effect and enhancement of electrical conductivity behavior as predicted from impedance measurements. For the temperature range of the current investigation, the temperature dependence of conductivity is found to obey the Davis‐Mott model.