Preparation and long-afterglow luminescence research of Sr 0.6 Ba 0.2 Ca 0.2 Al 2 O 4 ∶Eu, Dy

The Ca and Ba co-doped long afterglow phosphors Sr 0.6 Ba 0.2 Ca 0.2 Al 2 O 4 ∶Eu 2+ 0.01 , Dy 3+ 0.02 and only Ba doped phosphors Sr 0.6 Ba 0.4 Al 2 O 4 ∶Eu 2+ 0.01 , Dy 3+ 0.02 are synthesized by a high temperature solid-state reaction method. The phase structures of the phosphors are characterized by x-ray diffraction, showing that the crystal structures of samples are hexagonal. Photoluminescence spectra show that Eu 2+ ion acts as the only luminescence center in sample,and Sr 0.6 Ba 0.2 Ca 0.2 Al 2 O 4 ∶Eu 2+ , Dy 3+ display higher luminescent intensities due to the higher concentration of Eu 2+ ions in the host crystal lattice. The decay characteristics of phosphors show that Sr 0.6 Ba 0.2 Ca 0.2 Al 2 O 4 ∶Eu 2+ , Dy 3+ exhibit higher intensities in the initial afterglow process and longer afterglow time. The measurement of thermoluminescence reveals that the concentrations and depth of traps can be increased by Ca and Ba co-doping in Sr 0.6 Ba 0.4 Al 2 O 4 ∶Eu 2+ , Dy 3+ phosphor.