Tunable emission, energy transfer and charge compensation in Sr3(VO4)2:Sm3+,P5+,Na+ phosphor

A series of Sr-3(VO4)(2):Sm3+,P5+,Na+ phosphors are synthesized by using solid-state reaction method in air. The strongest emission band peaking at similar to 600 nm is assigned to the (4)G(5/2) -> H-6(7/2) transition of Sm3+ ion, and the strong excitation peak at similar to 402 nm due to H-6(5/2) -> F-4(7/2) transition indicates that these phosphors can be excited by near ultraviolet light emitting diode chip. Energy transfer (ET) between VO43- group and Sm3+ ion can be observed. Sr-3(VO4)(2):Sm3+ phosphor with excitation 320 nm exhibits a systematically varied hues from green to yellow by changing Sm3+ ion concentration from 0 to 6 mol%. The luminous mechanism of Sr-3(VO4)(2):Sm3+ phosphor is explained by using the energy level diagrams of VO43- group and Sm3+ ion. The luminescence properties of Sr-3(VO4)(2):Sm3+ phosphor can be improved and tuned by codoping the P5+ and Na+ ions due to ET and charge compensation. Lifetimes of Sr2.925Sm0.05(VO4)(2), Sr2.925Sm0.05(V0.9P0.1O4)(2), and Sr2.9Na0.05Sm0.05(V0.9P0.1O4)(2) phosphors are 1.208, 1.219, and 0.796 ms, respectively. The experiment results are helpful to adjust the luminescence properties of Sm3+-doped other phosphors. (C) 2015 Elsevier B.V. All rights reserved.