Krishnaraj Chidharth, Kaczmarek Anna M, Jena Himanshu Sekhar, Leus Karen, Chaoui Nicolas, Schmidt Johannes, Van Deun Rik, Van Der Voort Pascal
Institut für Chemie-Funktionsmaterialien , Technische Universität Berlin , Hardenbergstraße 40 , 10623 Berlin , Germany.
ACS Appl Mater Interfaces. 2019 Jul 31;11(30):27343-27352. doi: 10.1021/acsami.9b07779. Epub 2019 Jul 18.
Recently, covalent organic frameworks (COFs) have emerged as an interesting class of porous materials, featuring tunable porosity and fluorescence properties based on reticular construction principles. Some COFs display highly emissive monocolored luminescence, but attaining white-light emission from COFs is difficult as it must account for a wide wavelength range. White-light emission is highly desired for solid-state lighting applications, and obtaining it usually demands the combination of red-, green-, and blue-light components. Hence, to achieve the targeted white-light emission, we report for the first time grafting of lanthanides (Eu/Tb) on a two-dimensional imine COF (TTA-DFP-COF). We studied the luminescence properties of the hybrid materials prepared by anchoring Eu (red light) and Tb (green light) β-diketonate complexes onto the TTA-DFP-COF. Reticular construction is exploited to design strong coordination of Eu and Tb ions into nitrogen-rich pockets of the imine COF. Mixed Eu/Tb materials are then prepared to incorporate red and green components along with the inherent blue light from the organic moieties of the COF to produce white-light emission. We show that COFs have the potential for hosting Eu and Tb complexes, which can be tuned to obtain desired excitations for applications in the field of optoelectronics, microscopy, optical sensing, and bioassay.
最近，共价有机框架（COFs）已成为一类有趣的多孔材料，其基于网状结构原理具有可调的孔隙率和荧光特性。一些COFs表现出高发射单色发光，但从COFs获得白光发射却很困难，因为这必须考虑很宽的波长范围。固态照明应用非常需要白光发射，而获得白光通常需要红、绿、蓝光成分的组合。因此，为了实现目标白光发射，我们首次报道了在二维亚胺COF（TTA-DFP-COF）上接枝镧系元素（Eu/Tb）。我们研究了通过将Eu（红光）和Tb（绿光）β-二酮配合物锚定到TTA-DFP-COF上制备的杂化材料的发光特性。利用网状结构设计将Eu和Tb离子强配位到亚胺COF的富氮口袋中。然后制备混合的Eu/Tb材料，将红色和绿色成分与来自COF有机部分的固有蓝光结合起来，以产生白光发射。我们表明，COFs有潜力容纳Eu和Tb配合物，可对其进行调节以获得所需的激发，用于光电子学、显微镜、光学传感和生物测定领域的应用。
