State key Laboratory of Rare Earth Resource Utilization , Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022 , P. R. China.
University of Chinese Academy of Sciences , Beijing 100049 , P. R. China.
Inorg Chem. 2018 Oct 1;57(19):12303-12311. doi: 10.1021/acs.inorgchem.8b02025. Epub 2018 Sep 10.
In this article we synthesized a series of phosphors KMgGeO:Bi with high brightness for white light-emitting diodes (WLEDs) conversion and investigated their crystal structures and luminescence properties using powder X-ray diffraction, diffuse reflectance spectra, X-ray photoelectron spectroscopy, photoluminescence spectra, and absolute quantum efficiency. KMgGeO:Bi phosphor exhibits intense absorption in near-UV area and presents a broad asymmetric emission band with the main peak located at 614 nm, which was ascribed to the P → S transition of Bi. The absolute quantum efficiency of the KMgGeO:0.01Bi phosphor was measured to be 66.6%. Also, this orange emission with color chromaticity coordinates of (0.4989, 0.4400) has an excellent resistance to thermal quenching: its integrated intensity at 393 K still maintained ∼85% of the one at room temperature. The WLEDs devices with R = 93.8 were fabricated by employing KMgGeO:0.01Bi as an orange phosphor, which contains abundant red light component in its emission spectrum. The excellent luminescent performance of KMgGeO:0.01Bi suggests that it is a promising orange-emitting phosphor for near-ultraviolet WLEDs.
在本文中，我们合成了一系列具有高光效的用于白光发光二极管（WLEDs）转换的高亮度荧光粉 KMgGeO:Bi，并采用粉末 X 射线衍射、漫反射光谱、X 射线光电子能谱、荧光光谱和绝对量子效率研究了它们的晶体结构和发光性能。KMgGeO:Bi 荧光粉在近紫外区域具有强烈的吸收，并呈现出宽不对称的发射带，主峰位于 614nm，归因于 Bi 的 P → S 跃迁。KMgGeO:0.01Bi 荧光粉的绝对量子效率测量值为 66.6%。此外，这种橙色发射的色坐标为（0.4989，0.4400），具有出色的热猝灭抗性：其在 393K 时的积分强度仍保持室温下的约 85%。通过使用 KMgGeO:0.01Bi 作为橙色荧光粉，制备了色坐标为 R = 93.8 的 WLEDs 器件，其发射光谱中含有丰富的红光成分。KMgGeO:0.01Bi 的优异发光性能表明，它是一种有前途的近紫外 WLEDs 用橙色发光材料。
