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Pure and Eu 3+ -doped zinc sulfide (ZnS) crystallites were synthesized through a hydrothermal method using water and ethanol (W/E) as the solvent. The powder samples have been characterized systematically using a number of characterization techniques such as X-ray diffraction, scanning electron microscopy, energy-dispersive spectroscopy, photoluminescence spectroscopy, and UV–vis absorption spectroscopy. The band gap of ZnS and ZnS/ x Eu 3+ was calculated according to absorption spectroscopy, and an obvious red shift with the increasing molar fraction of Eu 3+ -doped ions was found. The luminescent mechanism of ZnS was explored by measuring the emission spectra of ZnS with different ratios of Zn and S. The emission spectra of ZnS/ x Eu 3+ included the characteristic emission peak of ZnS and Eu 3+ ions. The CIE chromaticity coordinates of the ZnS/ x Eu 3+ sample varied with the molar fraction of Eu 3+ ions. The emission intensity and morphology changed with the ratio of W/E in the process of hydrothermal reaction. The results indicate that the luminescence of the ZnS crystallite can be modulated by doping a certain amount of Eu 3+ ions, changing the ratio of Zn and S, or adding moderate ethanol as the reaction medium.

The upconversion luminescence agents Y2SiO5:Pr3+, Li+, that can be effectively excited by the blue light from a xenon lamp 150 W, are fabricated by a hydrothermal method with mesoporous molecular sieves of MCM-48 as the suitable silica source.