Effect of shock wave processing on the properties of ZnS and ZnS-based phosphors

Effect of shock wave treatment on luminescence of ZnS:Cu,Cl phosphors

“…3). Same effect of lattice constant decrease after shock wave treatment previously was observed for the undoped ZnS powders and was attributed to vacancies formation [4].…”

“…Luminescence spectra in this case show shift to shorter wavelengths due to the formation of Cu i -Cu Zn pairs and corresponding increase of relative intensity of emission band peaked at 450 nm. It is known that formation of such pairs may result from appearance of dislocations [4]. In addition to luminescence spectra, decay time of treated phosphors also changed, namely it gradually decreased from 1.2 ms for non-treated sample to 0.7 ms for sample treated with maximum energy.…”

“…Therefore there is a search for new approaches of improvements of their brightness. For example, we have suggested to use electron beam, plasma or shock wave treatment of ZnS and SrGa 2 S 4 precursors in order to create structural defects and thus improve diffusion and solubility of activator (copper) or sulfur in luminescent matrix and improve brightness [2][3][4][5][6]. In the works [7][8][9] it is suggested to fabricate phosphor in a highpressure vessel in the conditions of combustion and/or explosion of explosive substances, which is placed into a vessel together with a charge mixture.…”

Microwave synthesis of Eu-doped silicate phosphors

“…Thus, synthesis of phosphors for warm white light emitting diodes is an actual task nowadays. Recently new methods were applied to improve phosphor synthesis technology: utilization of plasma, shockwave treatment and microwave radiation [3][4][5][6]. Particularly in paper [6] it was demonstrated that synthesis of silicate phosphors in a microwave furnace provides a number of advantages compared with the conventional procedures (synthesis in muffle furnace in hydrogen atmosphere [7][8][9] and under the layer of coal [10,11]) including increased brightness as well as significantly reduced processing time and cost.…”

Microwave synthesis of Eu-doped silicate phosphors

“…Thus, synthesis of phosphors for warm white light emitting diodes is an actual task nowadays. Recently new methods were applied to improve phosphor synthesis technology: utilization of plasma, shockwave treatment and microwave radiation [3][4][5][6]. Particularly in paper [6] it was demonstrated that synthesis of silicate phosphors in a microwave furnace provides a number of advantages compared with the conventional procedures (synthesis in muffle furnace in hydrogen atmosphere [7][8][9] and under the layer of coal [10,11]) including increased brightness as well as significantly reduced processing time and cost.…”