Tuning of Photoluminescence by Cation Nanosegregation in the (CaMg)_x(NaSc)_1–xSi₂O₆ Solid Solution

Abstract

Controlled photoluminescence tuning is important for the optimization and modification of phosphor materials. Herein we report an isostructural solid solution of (CaMg)x(NaSc)1-xSi2O6 (0 < x < 1) in which cation nanosegregation leads to the presence of two dilute Eu(2+) centers. The distinct nanodomains of isostructural (CaMg)Si2O6 and (NaSc)Si2O6 contain a proportional number of Eu(2+) ions with unique, independent spectroscopic signatures. Density functional theory calculations provided a theoretical understanding of the nanosegregation and indicated that the homogeneous solid solution is energetically unstable. It is shown that nanosegregation allows predictive control of color rendering and therefore provides a new method of phosphor development.

Encaged-anion tunable luminescence of Ce3+-activated single host Ca12Al14O32Cl2 phosphor for UV pumped multi-color LEDs

“…Phosphor converted light-emitting diode (LED) is attracting significant attention as one of the most promising general illumination sources in recent years because of its advantages, such as low energy consumption, high efficiency, and long lifetime [1][2][3][4][5][6][7][8]. Common approaches to produce white light emitting diodes (WLEDs) include blending three primary colored phosphors with different hosts upon UV LED excitation or a combination of a blue LED emission with a single-host yellow phosphor [9][10][11][12][13].…”

High pressure studies of Eu2+ and Mn2+ doped NaScSi2O6 clinopyroxenes

“…Recent studies of NaScSi 2 O 6 :Eu 2+ and Mn 2+ clinopyroxene (this type of clinopyroxene is called jervisite) 6 and similar compounds showed that they might be useful as phosphors for WLED, being stable over a wide range of pressures and temperatures, exhibiting useful emission properties with possibility of tuning photoluminescence by using solid solutions between various compounds in clinopyroxene family. 6,7 Me 3+ ions are located in octahedral coordination in clinopyroxene host. It has been established with use of XRD data that Eu 2+ ions substitute Na ions in distorted cubic antiprism polyhedrons and Mn 2+ are in octahedral coordination replacing Sc ions.…”

New Y2BaAl4SiO12:Ce3+ yellow microcrystal-glass powder phosphor with high thermal emission stability

“…This process is also called ''chemical unit substitution''. 18,19 The phase formation temperature for Y 2 MAl 4 SiO 12 is also expected to decrease because of the M-Si pair introduction. An essential concern regarding such a design is whether the new phosphor can retain the garnet structure and whether the luminescence will be readily comparable to YAG:Ce; this paper presents the results of these two questions.…”