A novel strategy of constructing 2D supramolecular organic framework sensor for the identification of toxic metal ions

Two novel two-dimensional (2D) supramolecular organic frameworks were fabricated in water based on the encapsulation-enhanced donor-acceptor interaction between the methyl viologen (MV) units, methoxy naphthyl (MN) units, and CB [8]. The tetraphenylethylene (TPE) derivatives 1 with four MV units were employed as rigid building blocks and the two MN units modified oligoethylene glycol derivatives 2 and 3 served as flexible edges, respectively. The obtained two SOFs have obvious sheet-like structures and exhibit fluorescence emission at 350–500 ​nm. In addition, these two SOFs were employed for the luminescent detection of Cr(VI) and Mn(VII) in aqueous solutions, and the detection limits of CrO₄²⁻, Cr₂O₇²⁻, and MnO₄⁻ were calculated in a very low concentration range, indicating that these two SOFs can serve as a potential sensor for Cr(VI) and Mn(VII) detection in water. This work constructs two SOFs in an aqueous solution through a facile method and further enriches the applications of SOFs.