Hunan Provincial Key Laboratory of Environmental Catalysis and Waste Recycling, School of Chemistry and Chemical Engineering , Hunan Institute of Engineering , Xiangtan 411104 , China.
Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education of China), Key Laboratory of Sustainable Resources Processing and Advanced Materials of Hunan Province College , Hunan Normal University , Changsha 410081 , China.
ACS Appl Mater Interfaces. 2018 Nov 14;10(45):39064-39073. doi: 10.1021/acsami.8b14816. Epub 2018 Oct 30.
Exploring phosphors with high quantum efficiency (QE) and thermal stability is an important issue for their application in white light-emitting diodes (LEDs). In this work, the crystal structure and luminescent properties of Eu-activated aluminate phosphors with a normal composition (BaEuO)(AlO) (short for BAO:0.2Eu) were studied. Although the crystal structures of BAO:0.2Eu have a same space group, the increase of the Al content will lead to the decrease of cell volume, occupancy of Ba and O6 that is at around Ba1 site, and the increase of the average distance between Eu ions, which are responsible for the modification of luminescent properties. BAO:0.2Eu exhibits a blue-green emission with an emission peak at around 450 nm and a shoulder at around 490 nm. The increase of Al/(BaEu) ratio results in the increase of both absolute QE and thermal stability. The absolute QE of BAO:0.2Eu is 99.4%, and the emission intensity at 150 °C remains more than 90% of that at room temperature, showing the best performance. Furthermore, all of the external QE values of BAO:0.2Eu ( x = 0.2-0.5) are higher than 70%. The properties of the LEDs based on the as-prepared phosphor suggest its potential as a candidate for UV LED pumped phosphor-converted white LEDs.
探索具有高光量子效率 (QE) 和热稳定性的荧光粉对于其在白光发光二极管 (LED) 中的应用是一个重要的问题。在这项工作中，研究了组成正常的 Eu 激活的铝酸盐荧光粉 (BaEuO)(AlO)（简称 BAO:0.2Eu）的晶体结构和发光性能。尽管 BAO:0.2Eu 的晶体结构具有相同的空间群，但 Al 含量的增加会导致细胞体积减小、Ba 和 O6 在 Ba1 位的占有率降低以及 Eu 离子之间的平均距离增加，这些因素共同导致了发光性能的改变。BAO:0.2Eu 呈现出蓝绿色发射，发射峰位于 450nm 左右，同时在 490nm 左右有一个肩峰。Al/(BaEu) 比值的增加导致绝对 QE 和热稳定性都有所提高。BAO:0.2Eu 的绝对 QE 为 99.4%，在 150°C 时的发射强度保持在室温时的 90%以上，表现出最佳性能。此外，BAO:0.2Eu（x=0.2-0.5）的所有外量子效率值都高于 70%。基于所制备的荧光粉的 LED 的性能表明其有潜力成为 UV LED 激发的荧光粉转换白光 LED 的候选材料。
