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.