Synthesis and luminescence properties of a novel red-emitting LiSr4(BN2)3:Eu2+ phosphor

Abstract

A near-UV excited phosphor, LiSr₄(BN₂)₃:Eu²⁺ (LSBN:Eu²⁺), was synthesized using a solid-state reaction at 800 °C. The crystal structure of LSBN had been refined and determined from the XRD profiles by the Rietveld refinement method, which belongs to the space group Imm with the lattice constants a = b = c = 7.46112(23) Å. The excitation spectra of the LSBN:Eu²⁺ phosphors were centered at around 370 nm and covered the range from 300 to 450 nm. Under 400 nm excitation, the emission spectra of the LSBN:Eu²⁺ phosphors show a red emission centered at about 640 nm (FWHM ≈ 130 nm). And the energy transfer between the Eu²⁺ ions is confirmed to arise from the electric dipole–dipole interactions. The nontypical emission blue-shift in the single luminescence center with increasing temperature luminescence properties is also investigated. The results indicate that LSBN:Eu²⁺ could be conducive to the development of white light emitting diodes.