Luminescence, energy transfer and tunable color of Ce3+,Dy3+/Tb3+ doped BaZn2(PO4)2 phosphors

Abstract

Ce³⁺,Dy³⁺ and Tb³⁺ doped BaZn₂(PO₄)₂ phosphors were prepared via a high temperature solid state reaction route. The crystal structure, photoluminescence properties, decay lifetime, luminous efficiency and thermal stability of the phosphors were investigated. The mechanism of Ce³⁺–Dy³⁺/Tb³⁺ energy transfer was determined to be a dipole–dipole interaction based on the photoluminescence spectra and decay curves of the phosphors. The critical distance between the Ce³⁺ and Dy³⁺/Tb³⁺ ions was calculated using both the concentration quenching method and the spectral overlap method. Tunable emission from blue to bluish white and green can be realized by energy transfer and changing the doping concentrations of Dy³⁺ and Tb³⁺ under UV light. BaZn₂(PO₄)₂:Ce³⁺,Dy³⁺/Tb³⁺ phosphors are proved to be promising candidates in the lighting field due to their excellent thermal stability and luminescence properties.