Photoluminescence properties and energy transfer of Sr3Sc(BO3)3: Eu3+, Bi3+ phosphors

Abstract

A number of orange-red Sr3Sc(BO3)3 phosphors with Eu3+ single-doping and Eu3+, Bi3+ co-doping were successfully made using the high-temperature solid-state method. The morphology and composition of the samples were examined using X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), high-angle annular dark field (HAADF), and energy dispersive spectroscopy (EDS). Excitation and emission spectroscopy were used to investigate the characteristics of photoluminescence. In this work, Bi3+ are used as sensitizer to improve the emission intensity of Eu3+. The critical (or optimum) doping concentrations of Eu3+ and Bi3+ in Sr3Sc(BO3)3 were obtained experimentally (single-doping: 15 mol.% Eu3+, co-doping: 15 mol.% Eu3+, 0.3 mol.% Bi3+) to explore the energy transfer from Bi3+ to Eu3+. Under UV (393 nm) excitation, a strong orange-red luminescence corresponding to the 5D0→7F1 transition of Eu3+ can be observed, and a clear energy transfer from Bi3+ to Eu3+ can be discovered in the co-doped Sr3Sc(BO3)3. The energy transfer mechanism, as well as the CIE coordinates and decay lifetimes of a representative sample, are also discussed. The results show that Sr3Sc(BO3)3:Eu3+, Bi3+ is an orange-red phosphor with a higher efficiency under near-UV excitation.