A Study of Tb3+ → Eu3+ Energy Transfer in Tb3+/Eu3+ Codoped Y2Mg2Al2Si2O12 Phosphors

The work shows the design, fabrication and luminescence performance of garnet-structure Tb 3+ /Eu 3+ doped Y 2 Mg 2 Al 2 Si 2 O 12 phosphors. Upon the excitation, the representative emission of doping ions was observed. The Tb 3+ → Eu 3+ energy transfer in Tb 3+ /Eu 3+ codoped Y 2 Mg 2 Al 2 Si 2 O 12 phosphors was verified and surveyed via the measurements of luminescence and decay characteristics. The reducing intensity and lifetime of Tb 3+ emission following the growth of Eu 3+ concentration affirm the existence of Tb 3+ → Eu 3+ energy transfer. This process influences the emission color obviously. The energy transfer efficiency reaches 80.64% when the Eu 3+ concentration is 0.10. The energy transfer induces the changeable luminescence. The emitted lights move from green region to yellow-green, yellow, yellow-red and reddish regions gradually.