In this study we performed one-pot polycondensations of BFTB-4CHO with PyTA-4NH₂, BFTB-4NH₂, and BCTA-4NH₂ to prepare the bifluorenylidene-based covalent organic frameworks (COFs) BFTB–PyTA, BFTB–BFTB, and BFTB–BCTA, respectively. These three COFs possessed extremely high thermal stabilities, excellent crystallinities, and high specific surface areas. The BFTB–PyTA COF featured pores of a single size, whereas the BFTB–BFTB and BFTB–BCTA COFs had dual porosities. The COFs were exceptional adsorbers of the small dye molecule rhodamine B (RhB) in water; the maximum adsorption capacities reached as high as 2127 mg g⁻¹, outpacing those of all previously reported COFs, conjugated polymers, activated carbons, and other common nanoporous adsorbents. In addition, our COFs reached up to 99.2% of their maximum adsorption capabilities very rapidly (within 5 min). Furthermore, these COFs displayed good performance when used in electrodes for supercapacitors, with high stability after 2000 cycles. The superior adsorption efficiencies, ultrafast kinetics, and excellent reusability endow such COFs with tremendous potential for use as materials for removing RhB—and, presumably, other organic pollutants—from wastewater.

中文翻译：

---

基于异氟二芴基的共价有机骨架，表现出出色的染料吸附性能和高能量存储

在这项研究中，我们进行了BFTB-4CHO与PyTA-4NH ₂，BFTB-4NH ₂和BCTA-4NH ₂的一锅缩聚反应，以制备基于_二芴基的共价有机骨架（COF）BFTB-PyTA，BFTF-BFBF和BFTB–BCTA。这三个COF具有极高的热稳定性，出色的结晶度和较高的比表面积。BFTB–PyTA COF具有单一大小的孔，而BFTB–BFTB和BFTB–BCTA COF具有双重孔隙。COF是水中小染料分子若丹明B（RhB）的特殊吸附剂；最大吸附容量达到2127 mg g ^-1，超过所有先前报道的COF，共轭聚合物，活性炭和其他常见的纳米孔吸附剂。此外，我们的COF非常快地（在5分钟内）达到其最大吸附能力的99.2％。此外，这些COF在用于超级电容器的电极中时表现出良好的性能，在2000次循环后具有很高的稳定性。出色的吸附效率，超快的动力学性能和出色的可重复使用性使此类COF具有巨大的潜力，可用于从废水中去除RhB和其他有机污染物的材料。