A high efficiency blue phosphor BaCa2MgSi2O8:Eu2+ under VUV and UV excitation

Abstract

BaCa₂MgSi₂O₈:Eu²⁺ phosphors have been prepared by a conventional high temperature solid state reaction technique. The emission and excitation spectra as well as the luminescence decays were investigated, showing that Eu²⁺ ions enter both Ba²⁺ and Ca²⁺ sites in the host. The structural refinement reveals that about 70% Eu²⁺ ions occupy Ba²⁺ sites in samples Ba_1−xEu_xCa₂MgSi₂O₈ and BaCa_2(1−x)Eu_2xMgSi₂O₈. By investigation of the thermal-quenching, the schematic energy levels for Eu²⁺ in BaCa₂MgSi₂O₈ were proposed. Intense blue emission was observed under 147, 172 and 254 nm excitation in comparison with the commercial blue phosphor BaMgAl₁₀O₁₇:Eu²⁺ (BAM), demonstrating the potential application of the phosphors in plasma display panels (PDPs) and tri-color fluorescent tubes.