Tunable luminescence of Bi3+/Eu3+-doped SiO2–Al2O3-MCO3 (M = Ca, Sr, Ba) glasses for WLED

Abstract

In this work, a group of Bi3+/Eu3+-doped SiO2–Al2O3-MCO3 (M = Ca, Sr, Ba) glasses were fabricated through melt-quenching method. Their structure and photoluminescence characters were studied via X-ray diffraction (XRD), UV–Vis transmission spectra (TRS), excitation spectra, emission spectra and decay lifetimes. The XRD results show that no nano-crystal phase forms in glass matrix with different doping concentrations of Bi3+ and Eu3+ ions. Through regulating optical alkalinity value, the intensity of Bi3+ ions increases and the peak position shifts to red wavelength. The Bi3+/Eu3+ co-doped glasses show a blue-white-yellow-red luminescence by changing concentration of Eu3+ ions. Energy transfer efficiency from Bi3+ to Eu3+ can reach as high as 10.54%. At 423 K, the emission intensity of 55SiO2–10Al2O3–35BaO-0.25Bi2O3 (GBE0.5) is 31.1% of that at 308 K. Meanwhile, the activation energy of the glass matrix is 0.251 eV. All results suggest that these Bi3+/Eu3+ co-doped glass samples possess potential application in LED field.