Preparation and luminescent properties of orange reddish emitting phosphor LaMgAl11O19:Sm3+.

An orange reddish emitting phosphor, LaMgAl 11 O 19 :Sm 3+ , was synthesized by a high temperature solid-state reaction, and the phase formation, crystal structure and luminescence properties were investigated respectively. The LaMgAl 11 O 19 :Sm 3+ phosphor presents a highly intense orange reddish emission peak under the near ultraviolet excitation at 403 nm, which is corresponds to the 4 G 5/2 → 6 H J ( J = 5/2, 7/2, 9/2 and 11/2) transitions of Sm 3+ ions. It was found that the dipole–dipole interactions mainly results in the concentration quenching in the LaMgAl 11 O 19 :Sm 3+ phosphor with a critical quenching concentration at about 5 mol%. The temperature dependence of luminescence properties was studied from 25 to 200 °C and indicated that LaMgAl 11 O 19 :0.05Sm 3+ phosphors had a relatively higher quenching temperature. The chromatic properties of LaMgAl 11 O 19 :0.05Sm 3+ phosphor have been found to have chromaticity coordinate of (0.578, 0.420). All these properties indicate that the orange reddish emitting LaMgAl 11 O 19 :Sm 3+ phosphor has a potential application in w-LEDs. [ABSTRACT FROM AUTHOR]