Thermal plasma processing of technologically important materials

Thermal plasma is one of the upcoming powerful tools used for materials processing. It covers a wide range of technological applications such as synthesis of various refractory ceramic materials, metals and alloys, deposition of coatings, high temperature processing of materials as well as disintegration of waste materials. Representative technologically important material systems viz rare earth hexaboride (e.g. GdB₆) and carbonaceous materials are focus of the present manuscript. Both the material systems have been processed using DC thermal plasma route and characterized thoroughly for structural, morphological, surface properties using XRD, TEM, XPS respectively. Morphology of GdB₆ has been tailored by varying plasma parameters during synthesis. Further, these GdB₆ powder were investigated for electron emission performance using Field Electron Emission and maximum current density of 0.5 mA/cm² was noted for the nanocrystalline GdB₆ sample. Feasibility of thermal plasmas for production of nanocrystalline GdB₆ and processing of a bio-waste to obtain technologically important carbonaceous materials has also been explored.