Enhancement of luminescence and afterglow in CaTiO3:Pr3+ by Zr substitution for Ti

The photoluminescence and afterglow characteristics of Zr doped CaTiO3:Pr3+ phosphors were investigated. Zr4+ substitution for Ti4+ leads to the enhancement of red fluorescence and phosphorescence at 613 nm originating from 1D2 to 3H4 transition of Pr3+, and the increase of the lifetime for the 1D2 state. The enhancement of emission intensity was attributed to the change of the lattice structure, the increase of the Pr3+ amount, and the decrease of the concentration of the defects quenching red emission. The increase of lifetime was thought to originate from the increase of the density of [PrCa]0 traps.