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This thesis is a culmination of series of studies on the praseodymium activated alkaline earth sulfide phosphor synthesis through various routes and investigations on their luminescence properties. The phosphors were prepared via several methods namely solid-state carbothermal reduction, chemical co- precipitation where hydrazine-hydrate and sulfur solution acts as a workhorse behind a benchmark synthesis following post-precipitation annealing of precursors and solid-state sulfurization flux method utilizing alkali polysulfides to form the final product. Various experimental techniques such as photoluminescence, thermoluminescence, X-ray diffraction, Scanning electron microscopy and Time- resolved fluorescence decay measurements have been conducted to map the photophysical environment of such phosphors. The role of charge compensating defects and new excitation channels has been specially highlightened from this work. Such phosphors fit into myriad of significant technological optical applications like solid-state lighting, electroluminescence devices etc.

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The author sucessfully completed his Ph.D. and is presently pursuing postdoctoral research work on surface chemistry of phosphors at University of Free State, Bloemfontein, South Africa. He has published numerous research papers in reverred international journals having wide visibility and has recieved 4 best paper awards.

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