Energy transfer in co-and tri-doped Y3Al5O12 phosphors

Single-doped(Ce3+,Tb3+), co-doped(Ce3+-Tb3+, Ce3+-Yb3+, Tb3+-Yb3+) and tri-doped(Ce3+-Tb3+-Yb3+) Y3Al5O12phosphors were synthesized by a solid-state reaction method. The XRD, excitation and emission spectra and the fluorescence lifetime of the samples were measured. The energy transfer mechanism was also investigated. The results showed that the energy transfer efficiency from Tb3+to Ce3+was 51% and the energy transfer efficiency from Ce3+to Yb3+was 63.1%. Concomitantly, both were more efficient than that from Ce3+to Tb3+(7%) and from Tb3+to Yb3+(10.2%). Also, the Yb3+ions received energy mainly from Ce3+ions in Ce3+-Tb3+-Yb3+tri-doped Y3Al5O12phosphors. Among these materials, Ce3+-Yb3+co-doped YAG phosphors are a better choice than others as a down-conversion material due to their higher energy transfer efficiency.