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Recently, the preparation and characterization of materials in the nanometer scale has become challenging in the field of material science. Materials in the micrometer scale mostly exhibit physical properties as same as that of bulk form; however materials in the nanometer scale may exhibit physical properties distinctively different from that of bulk. Semiconducting nanoparticles have attracted widespread attention because of their special optical and electronic properties arising from the quantum confinement of electrons and large surface area. Among the semiconductor materials, Zinc Sulphide (ZnS), shows various luminescence properties such as photoluminescence, electroluminescence and thermoluminescence. Hence, ZnS is a traditional phosphor widely used in flat-panel display, electroluminescence devices, infrared windows, sensors and lasers. When ZnS material is doped with transition or rare earth metal ions, it is possible to modify its physical properties. For doped nanocrstalline semiconductor materials, quantum confinement effects in the energy states also produce unusual optical behaviour. In this book, undoped and some transition metal ions doped ZnS semiconducting nanomaterials were synthesized by microwave-assisted solvothermal method. To prepare the undoped ZnS nanoparticles, zinc acetate and thiourea were used as the precursor materials and ethylene glycol was used as the solvent. The solvothermal method used in this present work is an effective method for preparing metal sulfides under mild conditions, which is a simple, cheaper and convenient method. ZnS materials doped with transition metal ions were also synthesized by the same method. In the present work, ZnS material was doped with manganese, copper, cobalt and indium in four different concentrations. The microwave treated precursor materials, after washing with de-ionised water and acetone and after annealing leads to fine nanocrystalline powder. |
