Photoluminescence, transmittance and electrical properties of Eu3+-doped Al2O3-SrO glasses synthesized by an aerodynamic levitation technique

Abstract

A series of light green and transparent Eu3+-doped Al2O3-SrO glasses were synthesized by an aerodynamic levitation technique. The amorphous natures of the as-prepared glasses were confirmed by X-ray diffraction. The fluorescence excitation spectra of Al2O3-(3-x)SrO: xEu3+ glass phosphors showed an intense O2--Eu3+ charge transfer band at 268 nm. Under the excitation of 268 and 392 nm, these glasses phosphors emitted dominant red emission of Eu3+ (5D0–7F2 transition) at 615 nm. The chromaticity coordinates were found to be (x = 0.64, y = 0.36), which were corresponding to the red emission. The decay lifetime in the range of 1.228–1.250 ms hardly changed, indicating the concentration quenching effects were not obvious and Eu3+ activators barely underwent the energy migration. Furthermore, Eu3+-doped Al2O3-SrO glasses exhibited high transmittance of around 90% in the VIS–NIR region. They also had remarkable electric insulation performance (J up to 10−10–10–11A/cm2), excellent stable frequency of ε′ and low dielectric loss (10−4 −10−3). These findings show Eu3+-doped Al2O3-SrO glasses are multifunctional materials potentially applicable to near UV-based white LEDs as red-emitting components, optical devices and electronic packaging materials.