Li Jing-Ming, Huo Rui, Li Xia, Sun Hao-Ling
Department of Chemistry , Capital Normal University , Beijing , 100048 , China.
Department of Chemistry and Beijing Key Laboratory of Energy Conversion and Storage Materials , Beijing Normal University , Beijing 100875 , P. R. China.
Inorg Chem. 2019 Aug 5;58(15):9855-9865. doi: 10.1021/acs.inorgchem.9b00925. Epub 2019 Jul 23.
New Ln-metal-organic frameworks (Ln-MOFs), {[Ln(2,7-NDS)(IP)(OH)(HO)]·HO} [Ln = Sm , Eu , Gd , Tb , Dy , = 0.5-0; 2,7-NDS = 2,7-naphthalenedisulfonate, and IP = 1-imidazo[4,5-][1,10]-phenanthroline) were obtained by the hydrothermal method. The Ln-MOFs feature one-dimensional double chain structures. The photoluminescent properties of these complexes were investigated. Notably, the Eu-MOF exhibits a broad excitation band from 250 to 400 nm in the UV-vis region, and it presents red emission from the D → F transitions (where = 0-4) of the Eu ion. It is noteworthy that it still shows intense emission under near-visible irradiation at 350 nm < λ < 385 nm. Using the Eu-MOF as a luminescent sensor, the detection of Fe/Ag and ornidazole (ODZ)/ronidazole (RDZ) in aqueous medium was realized with long excitation wavelengths of 368 nm or even 385 nm in the near-visible region. This work provides a new approach to designing an efficient red emission with broad-band and near-visible light excitation and with luminescent chemosensor capability for biological applications. In addition, the Eu-MOF red light incorporated Gd-MOF blue-green light, and a white-light emission is realized based on a two-component GdEu doped complex. Magnetic studies of the Dy-MOF reveal that it has a single-molecule magnet and slow magnetic relaxation behavior with an energy barrier of 82.39 K.
新型镧系金属有机框架材料（Ln-MOFs），{[Ln(2,7-NDS)(IP)(OH)(HO)]·HO} [Ln = Sm 、Eu 、Gd 、Tb 、Dy ，= 0.5 - 0；2,7-NDS = 2,7-萘二磺酸盐，IP = 1-咪唑并[4,5-][1,10]-菲咯啉] 通过水热法制备得到。这些Ln-MOFs具有一维双链结构。对这些配合物的光致发光性质进行了研究。值得注意的是，Eu-MOF在紫外-可见区域呈现出从250到400 nm的宽激发带，并且从Eu离子的D→F跃迁（其中= 0 - 4）发出红色发射光。值得注意的是，在350 nm < λ < 385 nm的近可见光照射下它仍显示出强烈发射。以Eu-MOF作为发光传感器，在近可见光区域利用368 nm甚至385 nm的长激发波长实现了对水介质中Fe/Ag以及奥硝唑（ODZ）/甲硝唑（RDZ）的检测。这项工作为设计一种具有宽带和近可见光激发且具有用于生物应用的发光化学传感能力的高效红色发射提供了一种新方法。此外，Eu-MOF的红光与Gd-MOF的蓝绿光相结合，基于一种双组分GdEu掺杂配合物实现了白光发射。对Dy-MOF的磁性研究表明它具有单分子磁体以及能量势垒为82.39 K的慢磁弛豫行为。
