CAJ | 학술논문

高温固相法制备了（Ga1- x Alx ）2 O3∶Cr3＋（x＝0，0.1，0.2，0.3，0.4，0.5）系列荧光粉。X射线衍射分析表明Al3＋含量增加后，物相依然保持β-Ga2 O3的相。此外随着Al离子含量的逐渐增加，高衍射角峰位向右移动表明Al离子进入了β-Ga2 O3晶格中。激发光谱中258，300，410和550 nm左右的峰位分别对应基质Ga2 O3的带与带的吸收跃迁、电荷迁移带跃迁、Cr3＋的4 A2→4 T1以及4 A2→4 T2跃迁。随着Al离子掺杂量的增加，激发光谱峰位都呈现出不同程度的蓝移现象，这分别是由于基质的带隙能量、C r3＋与配体之间的电负性以及晶场强度增大所导致的。在发射光谱中，随着Al3＋替代Ga3＋，Cr3＋的发光由宽带发射变为窄带发射，这是由于Al3＋的掺入改变了Cr3＋周围的晶场，从而Cr3＋的红光发射由原来的4 T2→4 A2变为2 E→4 A2跃迁发射。Al离子掺杂改善了样品的长余辉发光特性，并且Al离子含量达到0.5时显示出较长时间的肉眼可见的近红外余辉发射。热释发光曲线显示材料中具有合适的陷阱能级，这也是材料产生长余辉发光的原因。
고온고상법제비료（Ga1- x Alx ）2 O3∶Cr3＋（x＝0，0.1，0.2，0.3，0.4，0.5）계렬형광분。X사선연사분석표명Al3＋함량증가후，물상의연보지β-Ga2 O3적상。차외수착Al리자함량적축점증가，고연사각봉위향우이동표명Al리자진입료β-Ga2 O3정격중。격발광보중258，300，410화550 nm좌우적봉위분별대응기질Ga2 O3적대여대적흡수약천、전하천이대약천、Cr3＋적4 A2→4 T1이급4 A2→4 T2약천。수착Al리자참잡량적증가，격발광보봉위도정현출불동정도적람이현상，저분별시유우기질적대극능량、C r3＋여배체지간적전부성이급정장강도증대소도치적。재발사광보중，수착Al3＋체대Ga3＋，Cr3＋적발광유관대발사변위착대발사，저시유우Al3＋적참입개변료Cr3＋주위적정장，종이Cr3＋적홍광발사유원래적4 T2→4 A2변위2 E→4 A2약천발사。Al리자참잡개선료양품적장여휘발광특성，병차Al리자함량체도0.5시현시출교장시간적육안가견적근홍외여휘발사。열석발광곡선현시재료중구유합괄적함정능급，저야시재료산생장여휘발광적원인。
The Al doping gallate phosphor (Ga1 - x Alx )2 O3 ∶Cr3+ (x=0 ,0.1 ,0.2 ,0.3 ,0.4 ,0.5) was synthesized by a high temperature solid-state reaction method .The X-ray diffractions show that the phase of the phosphors remains to be Ga2O3 struc-ture with increase in the contents of Al3+ ion .Beside ,the fact that the X-ray diffraction peak shifts towards big angles with in-creasing Al3+ ions content shows that Al3+ ions entered the Ga2 O3 lattice .The peaks of the excitation spectra located at 258 , 300 ,410 and 550 nm are attributed to the band to band transition of the matrix ,charge transfer band transition ,and 4 A2 → 4 T1 and 4 A2 → 4 T2 transition of Cr3+ ions ,respectively .Those excitation spectrum peak positions show different degrees of blue shift with the increase in the Al3+ ions content .The blue shift of the first two peaks are due to the band gap energy of substrate and the electronegativity between Cr3+ ions and ligands increasing ,respectively .The blue shift of the energy level transition of Cr3+ion is attributed to crystal field strength increasing .The Cr3+ ion luminescence changes from a broadband emission to a narrow-band emission with Al3+ doping ,because the emission of Cr3+ ion changed from 4 T2 → 4 A2 to 2 E→ 4 A2 transition with the crystal field change after Al3+ ions doping .The Al3+ ions doping improved the long afterglow luminescence properties of samples ,and the sample showed a longer visible near infrared when Al3+ ions content reaches 0.5 .The thermoluminescence curve shows the sample with suitable trap energy level ,and this is also the cause of the long afterglow luminescence materials .