Long afterglow from multi dopant transparent and opaque glass ceramic phosphor for white, red, yellow, and blue emissions: Zn2SiO4:Eu3+, Dy3+, Mn2+

In this paper, preparation of long afterglow phosphor with different emission colors in the system Zn2SiO4:Eu3+, Dy3+, Mn2+ was done via melt-quenching technique. The effect of adding mono-di-and tridopant on the phosphorescence properties was studied. Also, the effect of applying different heat treatment programs on the appearance of glass-ceramic (GC) to get transparent or opaque materials were optimized. DTA, XRD, SEM, UV-visible NIR, and fluorescence spectrophotometer were used to characterize the obtained materials. The results revealed crystallization of willemite and zinc borate; both Mn and Dy addition enhanced the degree of crystallization while Eu depressed it. Heat treatment at 650 degrees C/5 h revealed transparent glass-ceramic (TGC), above this temperature opaque glass-ceramic was appeared. Calculation of optical band gap (E-opt), Urbagh energy (Delta E) and refractive index were located in the range: 2.1-2.8 eV, 0.53-0.79 eV and 2.45-2.64 respectively. Lifetime decay was increased by increasing heat treatment temperature; it reaches similar to 2 h after irradiation at 260 nm for 30 min giving green emission at 558 nm. Visual appearance for the emitting light varies from white, red, yellow to blue color. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

In this study, long afterglow phosphors with different emission colors were prepared using the melt-quenching technique in the Zn2SiO4:Eu3+, Dy3+, Mn2+ system. The effects of doping elements and heat treatment on the optical properties were investigated. It was found that different heat treatment programs can result in transparent or opaque glass-ceramic materials.