Facile synthesis of Eu2+ activated dual light emitting barium silicate phosphors for warm-white light emitting diodes
Journal
Journal of Alloys and Compounds
Pages
1060-1064
Date Issued
2019
Author(s)
Abstract
Eu2+-ion-activated barium magnesium silicate phosphors were synthesized via a solid-state route with SiO2 and Si3N4 as silicon sources. The molar ratio of Si3N4 to SiO2 was varied from 0:1 to 3:1 for controlling the phase and luminescence emission of the synthesized materials. When Si3N4: SiO2 ratio was 0:1, efficient green emission around 513 nm was observed owing to the substitution of Eu2+ ions in Ba2MgSi2O7 lattice. With the increase of Si3N4: SiO2 molar ratio, a trigonal Ba3MgSi2O8 phase with blue emission was observed to coexist with monoclinic Ba2MgSi2O7 phase with green emission. Suitable dual emission was obtained for the phosphors synthesized with a Si3N4:SiO2 molar ratio of 0.8:1. White light emitting diodes (WLEDs) were fabricated by coating the optimized phosphors, and commercial red phosphors on InGaN ultraviolet (UV) LED chips. The electroluminescence spectra of the fabricated WLEDs exhibited near white chromaticity (0.34, 0.37) with high CRI of 94 and low CCT of 5213 K. The spectral characteristic results indicated a promising alkali silicate phosphor for UV LED application. © 2019
Subjects
Alkali silicate; Electroluminescence; Phosphor; Spectral characteristic; WLED
Other Subjects
Electroluminescence; Europium compounds; Gallium alloys; III-V semiconductors; Indium alloys; Light; Light emission; Light emitting diodes; Magnesium compounds; Molar ratio; Phosphors; Semiconductor alloys; Silica; Silicates; Silicon; Silicon oxides; Alkali silicates; Electroluminescence spectra; Luminescence emission; Spectral characteristics; Synthesized materials; White light emitting diodes; White lightemitting diodes (WLEDs); WLED; Barium compounds
Type
letter