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

Abstract A series of Sr 3 (VO 4 ) 2 :Sm 3+ ,P 5+ ,Na + phosphors are synthesized by using solid-state reaction method in air. The strongest emission band peaking at ∼600 nm is assigned to the 4 G 5/2  →  6 H 7/2 transition of Sm 3+ ion, and the strong excitation peak at ∼402 nm due to 6 H 5/2  →  4 F 7/2 transition indicates that these phosphors can be excited by near ultraviolet light emitting diode chip. Energy transfer (ET) between VO 4 3− group and Sm 3+ ion can be observed. Sr 3 (VO 4 ) 2 :Sm 3+ phosphor with excitation 320 nm exhibits a systematically varied hues from green to yellow by changing Sm 3+ ion concentration from 0 to 6 mol%. The luminous mechanism of Sr 3 (VO 4 ) 2 :Sm 3+ phosphor is explained by using the energy level diagrams of VO 4 3− group and Sm 3+ ion. The luminescence properties of Sr 3 (VO 4 ) 2 :Sm 3+ phosphor can be improved and tuned by codoping the P 5+ and Na + ions due to ET and charge compensation. Lifetimes of Sr 2.925 Sm 0.05 (VO 4 ) 2 , Sr 2.925 Sm 0.05 (V 0.9 P 0.1 O 4 ) 2 , and Sr 2.9 Na 0.05 Sm 0.05 (V 0.9 P 0.1 O 4 ) 2 phosphors are 1.208, 1.219, and 0.796 ms, respectively. The experiment results are helpful to adjust the luminescence properties of Sm 3+ -doped other phosphors.