Ln_3Al_5O_(12):Mn~(4+) (Ln = Y and Lu): non-rare-earth doped red phosphor for improving light properties of white light emitting diodes

摘要

Abstract We fabricated a series of Y~(3)Al~(5)O~(12):Mn_(4+)and Y~(1−y)Lu~(y)Al~(5)O~(12):Mn_(4+)phosphors by a solid state reaction. The phase and the optical properties of the synthesized phosphors were investigated. Under the excitation at 465 nm, Y~(3)Al~(5)O~(12):Mn_(4+)phosphors show emission bands locating at deep red regions, which is induced by the spin- and parity-forbidden_(2)E~(g) → _(4)A~(1g)transitions of Mn_(4+). The substitution of Y_(3+)by Lu_(3+)decreases the lattice parameter and thus strengthens the crystal field strength, which gives rise to the blue shift of emission band for Y~(1−y)Lu~(y)Al~(5)O~(12):Mn_(4+)phosphors. Due to the compensation of red light by Y~(3)Al~(5)O~(12):Mn_(4+)or Y~(1−y)Lu~(y)Al~(5)O~(12):Mn_(4+)phosphor, the values of correlated-color-temperature for fabricated LEDs are decreased, which leads to the suitable application for them in indoor illumination.