Preparation and wide band emission characteristics of Eu2+/Eu3+ co-doped Ba3P4O13 phosphors

Abstract

A series of phosphors Ba₃P₄O₁₃:xEu^2+/3+ (x = 0–0.1) were synthesized in a CO reduction atmosphere at a relatively low temperature (1113 K) by the solid-phase method. Crystallization and optical properties were investigated by using powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and fluorescence spectrophotometry (PL/PLE), respectively. Under the excitation of 394 nm, the emission spectrum of the phosphor presents a broad spectrum band of Eu²⁺ and characteristic peaks of Eu³⁺ in the range of 400–750 nm, indicating the coexistence of Eu²⁺ and Eu³⁺ in the system. The occupation of Eu²⁺ and Eu³⁺ in the Ba₃P₄O₁₃ matrix position was discussed by Gaussian fitting and PL spectra. The existence of energy transfer between Eu²⁺ → Eu³⁺ in the system can be found through PL spectra under excitation of 251 nm. The emission color of the phosphor can be adjusted by changing the Eu ion doping concentration, resulting in the CIE color coordinates changing from (0.213, 0.215) blue to (0.249, 0.261) light bluish white. The results show that Ba₃P₄O₁₃:Eu^2+/3+ phosphors can be used as a potential single-doped single-host white light-emitting material.