Luminescence Properties and Ce3+-> Tb3+ Energy Transfer in CaYAlO4:Ce3+, Tb3+ Phosphors

CaY1-x-yAlO4:xCe(3+), yTb(3+) phosphors arc synthesized by the sol-gel method. The effects of single-doped Ce3+ or Tb3+ rare earth ions and their co-doping on the luminescence properties of the phosphors arc discussed. The results show that the synthesized phosphors arc pure samples with the tetragonal structure. The CaY1-xAlO4 : xCe(3+) phosphors emit blue light peaking at around 445 nm under an excitation wavelength of 368 nm. The CaY1-yAlO4 : yTb(3+) phosphors emit green light peaking at 418, 440, 491, 548, 589, and 625 nm under an excitation wavelength of 246 nm. In Ce3+/Tb3+ co-doped phosphors, the energy transfers from Ce3+ to Tb3+, which makes the luminescence of Tb3+ enhanced. When the Ce3+ and Tb3+ co-doped phosphors arc under an excitation wavelength of 368 nm or 378 nm, Tb3+ emits a strong green light. The intensities of blue and green lights can be tuned by adjusting the doping concentrations of Ce3+ and Tb3+.