Gao Qiang, Li Xing, Ning Guo-Hong, Leng Kai, Tian Bingbing, Liu Cuibo, Tang Wei, Xu Hai-Sen, Loh Kian Ping
SZU-NUS Collaborative Innovation Center for Optoelectronic Science & Technology, Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China.
Chem Commun (Camb). 2018 Mar 1;54(19):2349-2352. doi: 10.1039/c7cc09866a.
The strong π-π interactions in the stacking layers of two-dimensional covalent organic frameworks (2D-COFs), together with rotationally labile imine linkages, make most of the solid state imine-linked COFs non-fluorescent due to fluorescence quenching processes. Here, we report the successful synthesis of highly photoluminescent imine-based 2D-COFs by integrating a non-planar building unit with a pyrene-based unit and transforming the COF into spherical, sub-micron particles. High photoluminescence quantum yields (PLQY) were achieved with COF sub-micron particles dispersed in organic solvents. The as-prepared COF sub-micron particles can be used as a chemical sensor for the detection of explosive chemicals, with high sensitivity and selectivity (up to ppm level).
二维共价有机框架（2D-COF）堆叠层中强烈的π-π相互作用，以及旋转不稳定的亚胺键，使得大多数固态亚胺连接的COF由于荧光猝灭过程而不具有荧光。在此，我们报告了通过将非平面构建单元与芘基单元整合，并将COF转化为球形亚微米颗粒，成功合成了高光致发光的亚胺基2D-COF。将COF亚微米颗粒分散在有机溶剂中可实现高光致发光量子产率（PLQY）。所制备的COF亚微米颗粒可用作检测爆炸物的化学传感器，具有高灵敏度和选择性（高达ppm水平）。
