Color-tunable and highly thermal stable Sr2MgAl22O36:Tb3+ phosphors

Abstract Tb 3+ activated Sr 2 MgAl 22 O 36 phosphor was prepared by a high-temperature solid-state reaction route. The X-ray diffraction, scanning electron microscopy, and photoluminescence spectroscopy were used to characterize the as-prepared samples. The Sr 2 MgAl 22 O 36 :Tb 3+ phosphors show intense green light emission under UV excitation. The phosphor exhibit two groups of emission lines from about 370 to 700 nm, which originating from the characteristic 5 D 3 - 7 F J and 5 D 4 - 7 F J transitions of the Tb 3+ ion, respectively. The cross-relaxation mechanism between the 5 D 3 and 5 D 4 emission was investigated and discussed. The emission colors of these phosphors can be tuned from bluish-green to green by adjusting the Tb 3+ doping concentration. Furthermore, the thermal quenching temperature ( T 1/2 ) is higher than 500 K. The excellent thermal stability and color-tunable luminescent properties suggest that the developed material is a promising green-emitting phosphor candidate for optical devices.