Manganese activated (2-x)ZnO DT xCdO DT 1.1SiO2 phosphors obtained by solid state synthesis

The aim of the work was to study the evolution of luminescence emission properties of some Mn2+ activated phosphors in the ZnO-CdO-SiO2 system in correlation with both the cadmium oxide/zinc oxide mole ratio and the activator concentration. A number of phosphors corresponding to the mole target composition of (2-x)ZnO DT xCdO DT 1.1SiO2:yMn, where 0 # < x # < 0.15, and y = 0.021; 0.042; 0.085, were obtained by firing the mixed powders of precursors (oxides and carbonates), at 1250DGC or 1350DGC temperatures, in air, for 60 minutes. Thermal analysis technique was used in order to elucidate the oxide system behaviour during thermal treatment. Structural and optical properties were investigated by X-ray diffraction and spectrofluorometry techniques All obtained samples show a green luminescence emission, as if was expected for manganese-activated willemite. The emission intensity of the synthesized phosphors seems to be influenced by host matrix composition and activator amount, as well. It was observed that, in the domain of relatively low CdO/ZnO mole ratio, regardless the activator concentration, the emission intensity is favorable influenced by CdO content, the maximum being reached for the composition 1.975ZnO DT 0.025CdO DT 1.1SiO2-0.085Mn.