Luminescence and energy transfer in BaY2(MoO4)4:Tb3+, Eu3+ phosphors and bifunctional applications in thermometry and light emitting diodes

A series of BaY2(MoO4)(4):Tb3+, Eu3+ phosphors were synthesized by solid state reaction. The phase purity, crystal structure and photoluminescence properties were identified by X-ray diffraction, SEM, DRS, excitation and emission spectra, and luminescence decay curves. The emission color can be tuned from green to yellow and then to red by changing the concentration ratio of Eu3+ and Tb3+ under near-UV excitation. The energy transfer processes between Eu3+ and Tb3+ ions were investigated on the basis of emission spectra under different excitation wavelength. BaY2(MoO4)(4):Tb3+, Eu3+ phosphors exhibited high temperature sensing performance in the temperature range of 89-293 K with maximum absolute sensitivity of 6.02% K-1 and relative sensitivity of 1.06% K-1. The fabricated LEDs presented good performance in the light emitting field with low CCT of 3875 K and high Ra of 82.1 lm/W.