Luminescence properties and energy transfer of Tb3+, Eu3+co-doped YTaO4phosphors obtained via sol-gel combustion process

Tantalate is considered as a valuable and efficient luminescence host because of its intense absorption in the ultraviolet area and excellent chemical properties. In this work, a series of pure YTaO4:Eu(3+)and/or Tb(3+)crystals were prepared via a sol-gel combustion method. The morphology, structure, and optical properties of the samples were discussed in detail. The Eu3+, Tb(3+)co-doped YTaO(4)samples are consisted of small spherical particles of around 18 nm. The prepared YTaO4:Tb(3+)and/or Eu(3+)samples exhibit the characteristic wide excitation band around 210-300 nm, the characteristic narrow red emission of Eu3+(D-5(0) -> F-7(2)) transitions and green emission of the Tb3+(D-5(4) -> F-7(5)) transitions when excited by UV light. It is focused on the energy transfer processes from the YTaO(4)to Tb(3+)as well as Eu(3+)ions and from Tb(3+)to Eu(3+)ions of YTaO4:Eu3+/Tb(3+)phosphors. Color-tunable emissions are realized through adjusting the types of rare earth ion (Eu(3+)and Tb3+) and relative doping concentrations excited by a single wavelength. That is to say, the obtained Tb(3+)and Eu(3+)co-doped YTaO(4)phosphors have a promising prospect in lasers, white light diodes (WLED), fluorescent lamp, and field emission display devices, etc.