Combustion synthesis and photoluminescence of ZnS:Mn particles

An efficient process based on a solid-state combustion technique has been developed to produce high crystalline and micrometer sized particles of ZnS:Mn⁺² phosphor with sphalerite structure. The precursor mixture of 0.915Zn+S+0.05Mn+0.035ZnCl₂+kNaCl composition (where k is the mole number of NaCl) was combusted under the argon atmosphere followed by post-heat treatment procedure at 700 °C. It was shown that photoluminescence (PL) intensity of ZnS sample can be easily controlled through adjusting NaCl concentration. In the optimized reaction conditions ZnS samples have showed PL intensity almost comparable to that of a commercial one, despite the relatively low purity of precursor materials used. Many interesting phenomena such as high luminescent efficiency, pure cubic ZnS formation after the post-heat treatment and strong influence of Cl⁻ ion on PL intensity have been observed and discussed.