Luminescent properties of single-phase Ba 2-x-1.5y-1.5z P 2 O 7 :xEu 2+ ,yCe 3+ , zTb 3+ phosphors for white light-emitting diode.

A series of Ba2 P2 O7 :xEu2+ ,yCe3+ ,zTb3+ phosphors was synthesized via a co-precipitation method, then their crystal structure, quantum efficiency and luminescent properties were analyzed by XRD and FL, respectively. The results showed that these phosphors not only presented the excitation characteristics of Ba2 P2 O7 :xEu2+ ,zTb3+ , but also exhibited that of the Ba2 P2 O7 :yCe3+ ,zTb3+ phosphor. Meanwhile, the tri-doped phosphor showed a stronger absorption around 320 nm in contrast with the Eu2+ /Ce3+ :Tb3+ co-doped phosphor. Not only can energy transfer from Ce3+ →Eu2+ be observed; the energy transfer mechanism from Eu2+ to Tb3+ is discussed in the tri-doped system. Ce3+ affects the luminescence properties of Ba2 P2 O7 :xEu2+ ,yCe3+ ,zTb3+ phosphors just as the sensitizer whereas Eu2+ is considered both as the sensitizer and the activator. The chromaticity coordinates of tri-doped phosphors excited at 320 nm stayed steadily in the bluish-white light region,and the emitted color and color temperature (CCT) of these phosphors could be tuned by adjusting the relative contents of Eu2+ , Ce3+ and Tb3+ . Hence, the single phase Ba2 P2 O7 :xEu2+ ,yCe3+ ,zTb3+ phosphors may be considered as potential candidates for white light-emitting diodes.