Effect of Killer Impurities on Laser Excited Doped ZnS Phosphors

Zinc sulphide phosphors, doped with Ba and Mg as well as killer impurities of Fe, Co and Ni having variable concentrations have been synthesized and then using ultraviolet laser (Nitrogen Laser) as the excitation source, their decay-curve analysis has been done. Various strong emissions have been detected and the corresponding excited state lifetimes are measured at room temperature. Studies have also been carried out to see the effect of different dopant concentrations on the phosphorescence excited-state life times.