Effect of co-doped metal caions on the properties of Y2O3：Eu3＋ phosphors synthesized by gel-combustion method

Y2O3：Eu3＋ phosphors co-doped with different metal cations （Li＋, Na＋, K＋, Mg2＋, Ca2＋） are prepared by the gel- combustion method with Y2O3：Eu3＋, and R（NO3）x （R = Li, Na, K, Mg, Ca） serving as raw materials and glycine as fuel, calcined at 1000 ℃ for 2 h. The synthesized Y203 ：Eu3＋ phosphors doped with different metal cations and doping ratios are characterized by x-ray diffractometry （XRD）, fluorescence and phosphorescent spectrophotometer. The co-doping metal cations are advantageous to the development of Y203：Eu3＋ lattice. All the samples can emit red light peaked at 611 nm under 254-nm excited. The luminescence intensities of co-doping samples are increased because the cations increase the electron transition probability of Eu3＋ from 5D0 level to 7F level. The fluorescence lifetime of Eu3＋ （SD0 --＋7F2） is increased by doping metal cations.