Luminescence characteristics of NaYGeO4:Bi3+/Tb3+/Eu3+ phosphors

A series of Bi 3+ /Tb 3+ /Eu 3+ doped NaYGeO 4 phosphors were synthesized via the solid state sintering at 1300 °C for 3 h. The phase and luminescence performance of the synthesized phosphors were investigated. The Bi 3+ , Tb 3+ and Eu 3+ single doped NaYGeO 4 phosphors show the prominent blue, green and red emission, respectively. And the emission shows obvious dependence on doping concentration and excitation wavelength. The Bi 3+ → Tb 3+ /Eu 3+ energy transfers were confirmed by the luminescence characteristics of the Bi 3+ /Tb 3+ , Bi 3+ /Eu 3+ and Bi 3+ /Tb 3+ /Eu 3+ doped NaYGeO 4 phosphors. The Bi 3+ → Tb 3+ energy transfer in the NaYGeO 4 :Bi 3+ /Tb 3+ phosphors leads to the tunable emission from the blue to cyan-green light region and the Bi 3+ → Eu 3+ energy transfer in the NaYGeO 4 :Bi 3+ /Eu 3+ phosphors leads to the tunable emission from the blue to purple-red light region. But in the NaYGeO 4 :Bi 3+ /Tb 3+ /Eu 3+ phosphors, the Bi 3+ → Tb 3+ /Eu 3+ energy transfers lead to the tunable emission from the blue to yellow light region through the white light region. From the luminescence characteristics of the Bi 3+ /Tb 3+ /Eu 3+ doped NaYGeO 4 phosphors, the energy transfer mechanisms were speculated. • The excellent luminescence characteristics for the NaYGeO 4 based phosphors. • Dual energy transfer induced white light for the NaYGeO 4 :Bi 3+ /Tb 3+ /Eu 3+ phosphors. • The wide tuning range of the doping concentration for the white light phosphors.