Fabrication and optical properties of ZnS:Mn2+ quantum dots/SiO2 nanocomposites

ZnS:Mn2+ quantum dots (QDs)/SiO2 nanocomposites were successfully synthesized by stober method. The results showed that the Mn2+ ions were substitutionally incorporated into the ZnS host and the average size of the ZnS:Mn2+ (5 %) QDs was about 5.5 nm. The yellow-orange emission from the Mn2+ T-4(1)-(6)A(1) transition was observed in the photoluminescence spectra, the peak intensity increased as the Mn2+ doped ratio increased, and showed a maximum when the concentration of the Mn2+ ions kept at 3 %. As the hydrolysis time of tetraethyl orthosilicate increased, the intensity of the yellow-orange emission reached the highest value when t = 4 h for the ZnS:Mn2+ (5 %) QDs/SiO2 nanocomposites.