Enhanced Eu3+ emission in Ca2LaTaO6:Eu3+ phosphors by codoping Bi3+

The Bi3+/Eu3+ singly and codoped double perovskite Ca2LaTaO6 phosphors were made via solid-phase sintering with the addition of H3BO3. X-ray powder diffraction patterns, morphology, particle size, and photoluminescence properties of them were researched. All of Bi3+/Eu3+ singly and codoped Ca2LaTaO6 phosphors have the same phase with pure Ca2LaTaO6. And all of phosphors have similar morphology and particle size. Exciting at 275 nm, Ca2La1-xEuxTaO6 (x = 0.1, 0.2, 0.3, 0.4, and 0.5) phosphors exhibit bands resulting from D-5(0) -> F-7(J) (J = 0, 1, 2, 3, and 4) transitions of Eu3+. It is found that the critical doping concentration of Eu3+ in Ca2LaTaO6 is about 0.4. Exciting at 272 nm, Ca2La1-yBiyTaO6 (y = 0.05, 0.1, and 0.15) phosphors exhibit emission bands corresponding to the P-3(1) -> S-1(0) transition of Bi3+. There is the occurrence of energy transfer in Bi3+/Eu3+ codoped Ca2LaTaO6 phosphors, which benefits to the enhancement of Eu3+ emission intensity.