We present time-lapsed microscopy and EXAFS/XANES data on size selected ground ZnS:Cu,Cl and ZnS:Cu,Mn,Cl phosphors to probe long standing problems in using these phosphors in high brightness applications. The time-lapsed study shows that many of the individual emission centers on each particle degrade via large step decreases while < 50% have a monotonic decrease. These large steps suggest a b...

This review article summarizes the recent achievements in stabilization of the metastable lattice of gadolinium aluminate garnet (Gd3Al5O12, GAG) and the related developments of advanced optical materials, including down-conversion phosphors, up-conversion phosphors, transparent ceramics, and single crystals. Whenever possible, the materials are compared with their better known YAG and LuAG cou...

Y2O3:Eu were prepared through precursors synthesized by leaching tests, removing impurities, enrichment of Y and Eu from residual purified liquors, annealing treatment, and high temperature solid-state reaction method, which is the most suitable for large-scale production. The analysis of product shows that the purity is 99.42%. The resultant powders were characterized by X-ray diffraction (XRD...

In this combined X-ray diffraction and photoluminescence study, the coordination environment of Mn(2+) and the photoluminescence of single Mn(2+) doped KMgBO3 phosphors were studied. Mn(2+) occupies Mg(2+) sites, which were coordinated by six O(2-). The strong absorption of KMgBO3:Mn(2+) was ascribed to the strong relaxation of spin and parity forbidden d-d transitions of Mn(2+). The emission b...

Alternating current thin-film electroluminescent (AC-TFEL) devices already occupy a segment of the large-area, high-resolution, flat-panel-display market. The AC-TFEL displays, which consist of a phosphor layer, such as manganese doped-zinc sulfide (ZnS:Mn), vertically sandwiched between two insulators that are contacted by electrodes, are robust, possess long lifetimes, and offer high luminanc...

In this paper, Zn2SiO4:xEu3+ phosphors were synthesized with different concentrations of Eu3+ ions (x = 1, 3 and 5 wt.%) by using waste bottle glasses as silicate source. The structure, morphology, and luminescent properties of the phosphors were characterized using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and photoluminescence (PL) spectroscopy. The XRD ana...

We demonstrate silicon-based phosphor materials which exhibit bright photoluminescence from near-infra-red to green. The colloidal composites which are composed of silicon quantum dots (SiQDs) attached on micro-size silicon particles are synthesized by electrochemical etching of silicon wafers and then dispersed in ethanol. Subsequently, isotropic etching by HF/HNO3 mixture controls the size so...

Nitridosilicates are structurally built up on three-dimensional SiN4 tetrahedral networks, forming a very interesting class of materials with high thermomechanical properties, hardness, and wide band gap. Traditionally, nitridosilicates are often used as structural materials such as abrasive particles, cutting tools, turbine blade, etc. Recently, the luminescence of rare earth doped nitridosili...

The spectral response, brightness, and outgassing characteristics of new, low-voltage phosphors for application in field emission flat panel displays, are presented. The tested phosphor materials include combustion synthesized powders and thin films prepared by rf diode or magnetron sputtering, laser ablation, and molecular beam epitaxy. These cathodoluminescent materials are tested with e-beam...