Luminescence properties and energy transfer of K 3 LuF 6 :Tb 3+ ,Eu 3+ multicolor phosphors with a cryolite structure.

In recent years, compounds with a cryolite structure have become excellent hosts for luminescent materials. In this paper, Tb 3+ doped and Tb 3+ /Eu 3+ co-doped K 3 LuF 6 phosphors were prepared via a high temperature solid phase sintering method. The XRD, SEM, as well as photoluminescence excitation (PLE) and emission (PL) spectra were measured to investigate the structure and luminescence properties of the as-prepared samples. In the Tb 3+ /Eu 3+ co-doped K 3 LuF 6 samples, both characteristic emission spectra of Tb 3+ and Eu 3+ could be observed and the emission color of the K 3 LuF 6 :0.12Tb 3+ , x Eu 3+ phosphors could be adjusted from green to yellowish pink and the corresponding CIE values could be regulated from (0.2781, 0.5407) in the green area to (0.4331, 0.3556) in the yellowish pink area by controlling the concentration ratio of Eu 3+ /Tb 3+ . In addition, the energy transfer mechanism in Tb 3+ /Eu 3+ co-doped K 3 LuF 6 was calculated to be a quadrupole-quadrupole interaction from Tb 3+ to Eu 3+ based on the Dexter's equation.