Molten salt synthesis and luminescence performance of the Ce3+/Eu2+ doped Sr3Y2Ge3O12 phosphors

Abstract

The Ce3+ and/or Eu2+ doped inorganic phosphors with the broad excitation bands and efficient visible emission play the important roles in the light emitting diodes. Herein, we synthesized the Ce3+/Eu2+ doped Sr3Y2Ge3O12 phosphors via a molten salt method under a reducing atmosphere. The phosphors were investigated by the X-ray diffraction, scanning electron microscopy, transmission electron microscopy and fluorescence spectrophotometer. The thermal stability of the Sr2.91Ce0.03Eu0.06Y2Ge3O12 phosphor was evaluated in 300–500 K at a temperature interval of 25 K. Upon the excitation at 450 nm, the Sr2.97Ce0.03Y2Ge3O12 and Sr2.97Eu0.03Y2Ge3O12 phosphors emit green and yellow-red light, respectively. The energy transfer process from Ce3+ to Eu2+ occurs in Ce3+/Eu2+ codoped Sr3Y2Ge3O12 phosphors, which results in the tunable luminescence.