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

A series of Bi3+/Tb3+/Eu3+ doped NaYGeO4 phosphors were synthesized via the solid state sintering at 1300 ? for 3 h. The phase and luminescence performance of the synthesized phosphors were investigated. The Bi3+, Tb3+ and Eu3+ single doped NaYGeO4 phosphors show the prominent blue, green and red emission, respectively. And the emission shows obvious dependence on doping concentration and excitation wavelength. The Bi3+ -> Tb3+/ Eu3+ energy transfers were confirmed by the luminescence characteristics of the Bi3+/Tb3+/Eu3+/Eu3+ and Bi3+/ Tb3+/Eu(3+)doped NaYGeO(4 )phosphors. The Bi3+ -> Tb3+ energy transfer in the NaYGeO4:Bi3+/Tb3+ phosphors leads to the tunable emission from the blue to cyan-green light region and the Bi3+ -> Eu3+ energy transfer in the NaYGeO4:Bi3+/Eu3+ phosphors leads to the tunable emission from the blue to purple-red light region. But in the NaYGeO4:Bi3+/Tb3+/Eu3+ phosphors, the Bi3+ -> Tb3+/Eu3+ 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 Bi3+/ Tb3+/Eu(3+)doped NaYGeO4 phosphors, the energy transfer mechanisms were speculated.

Automated summary

A series of Bi3+/Tb3+/Eu3+ doped NaYGeO4 phosphors were synthesized. The emission of the phosphors is dependent on the doping concentration and excitation wavelength, showing potential for tunable emission from blue to different regions. Energy transfer mechanisms between Bi3+ and Tb3+/Eu3+ were speculated based on the luminescence characteristics.