Phase-Dependent Thermoluminescence Properties of Zinc Sulphide

In the current study, the effects of heat treatment on the thermoluminescence (TL) and structural properties of zinc blend samples were studied. The samples were annealed after being heated for different time periods from 2 up to 10 h. The wurtzite hexagonal phase was observed upon heat treatment. It was observed that the presence of hexagonal phase with small percentage enhanced the thermoluminescence effect where the highest intensity was found to be for the sample with 8.2% wurtzite and 91.8% cubic zinc sulphide. The morphology of ZnS particles was studied by the HR-TEM analysis and it displayed an aggregated ZnS nanoparticles with almost uniform shape and size. The TL-glow curves for each sample were analysed using the Computerized Glow Curve Deconvolution (CGCD) and initial rise (IR) methods. Six trapping peaks exist between 0.98 and 1.45 eV through the deconvolution process. The number of peaks increased to 8 peaks for the fourth treatment, located between 0.95 and 1.56 eV. The activation energies and the frequency factors for getting traps were evaluated too.