Improved luminescence of YPO4:Eu3+ phosphors by codoping Ca2+

YPO4:Eu3+/Ca2+ phosphors were synthesized by the solid state reaction. The XRD and FTIR results indicate that the obtaining YPO4:Eu3+/Ca2+ samples have the tetragonal zircon structure. Under the excitation of 307 nm, YPO4:Eu3+/Ca2+ phosphors show characteristic emission bands of Eu3+ originating from the 5D0 → 7Fj (j = 1, 2, 3, and 4) transitions. The codoping Ca2+ concentrations have obvious influence on the luminescence intensities and decay lifetimes. The luminescence intensity reaches the maximum value when the codoping Ca2+ concentration is 5 mol% and decreases with further increasing Ca2+ concentration. The decay lifetimes decrease with increasing Ca2+ concentrations.