Excitation band extended in CaYAl3O7: Tb3+ phosphor by Ce3+ co-doped for NUV light-emitting diodes

Abstract

A series of CaYAl3O7: Ce3+, Tb3+ phosphors has been synthesized by combustion method for the first time. XRD measurements demonstrated the phosphor hosts keep pure tetragonal crystalline structure at 850°C. The photoluminescence properties of Tb3+, Ce3+ singly and co-doped CaYAl3O7 have been discussed. Under the Ce3+ excitation at 360nm, enhanced green emission was obtained in Ce3+ co-doping CaYAl3O7: Tb3+ sample. And combining the photoluminescence properties and fluorescence decay curves, energy transfer from Ce3+ to Tb3+ was investigated and a possible mechanism was proposed. The results indicate that CaYAl3O7: Ce3+, Tb3+ phosphors have potential applications as a kind of near ultraviolet-convertible green phosphor for white light-emitting diodes by Ce3+ co-doped which perfectly makes excitation band of Tb3+ extend from 243 to 360nm.