A strong red-emitting carbazole based europium(iii) complex excited by blue light
作者:P. He、H. H. Wang、H. G. Yan、W. Hu、J. X. Shi、M. L. Gong
DOI:10.1039/c0dt00424c
日期:——
A novel 2-positional linked carbazole based β-diketone with methoxyl in the 7-position (EMOCTFBD), and its europium(III) ternary complex Eu(EMOCTFBD)3phen were synthesized via a dexterously designed indirect routine, where EMOCTFBD was 1-(9-ethyl-7-methoxyl-9H-carbazol-2-yl)-4,4,4-trifluorobutane-1,3-dione and phen was 1,10-phenanthroline. Eu(EMOCTFBD)3phen shows high thermal stability. The introduction of a methoxyl in the 7-position of the carbazole ring remarkably enhanced the excitation band intensity in the blue region, and the complex exhibited intense red emission under blue-light excitation. The lowest triplet state energy was measured and suggests the photoluminescence process as a ligand-sensitized luminescence process (antenna effect). A bright red-emitting diode was fabricated by coating the complex phosphor onto a ∼460 nm-emitting InGaN chip. All the results indicate that Eu(EMOCTFBD)3phen is an interesting red-emitting material excited by blue light, and therefore may be applied in many fields without UV radiation.
通过巧妙设计的间接程序合成了一种新型 2 位连接的咔唑基 β-二酮(7 位为甲氧基)(EMOCTFBD)及其铕(III)三元配合物 Eu(EMOCTFBD)3phen,其中 EMOCTFBD 为 1-(9-乙基-7-甲氧基-9H-咔唑-2-基)-4,4,4-三氟丁烷-1,3-二酮,phen 为 1,10-菲罗啉。Eu(EMOCTFBD)3phen具有很高的热稳定性。在咔唑环的 7 位引入甲氧基后,蓝色区域的激发带强度显著增强,在蓝光激发下,该配合物呈现出强烈的红色发射。测量到的最低三重态能量表明,该光致发光过程是一种配体敏化发光过程(天线效应)。通过将复合荧光粉涂覆到发射波长为 460 nm 的 InGaN 芯片上,制备出了明亮的红色发光二极管。所有这些结果表明,Eu(EMOCTFBD)3phen 是一种由蓝光激发的有趣的红色发光材料,因此可以应用于许多没有紫外线辐射的领域。