Effect of Heat Treatment on the Optical and Structural Properties of CdS: Tb Nanoforms

Abstract

CdS is an important II-VI semiconductor and has been highlighted as an efficient emitter because of its high quantum yield and direct band gap in the visible range. CdS:Tb nanorods have been synthesized using Solvothermal technique using ethylenediamine as the organic solvent. The samples have been heat treated at 200o C for 2 hours in nitrogen gas atmosphere and the effect on the structural, and optical properties have been studied. The crystal structure and the average crystallite size of the samples have been calculated using X-ray diffraction pattern. The morphology of the nanorods has been studied through SEM images. The elemental analysis has been carried out by EDAX spectroscopy and the FTIR spectroscopy reveals the chemical components on the surface of the nanorods. The band gap of CdS:Tb nanorods, as-synthesized and heat treated, has been calculated by UV-Visible absorption spectra. Room temperature PL studies have been carried out to study the emission characteristics of the synthesized nanoforms. No structural changes have been observed in XRD patterns. But changes have been observed in morphological and optical characterization with doping and heat treatment.