Luminescent Detection of Cr(VI) and Mn(VII) Based on a Stable Supramolecular Organic Framework

A new fluorescent supramolecular organic framework (HNU-35) has been constructed, which is a three-dimensional structure composed of hydrogen bonding interactions between the carboxyl groups of adjacent 1,1,2,2-tetrakis(4-carboxyphenyl)ethylene (H4TCPE). HNU-35 exhibits good acid–base stability and can be stable in the pH range of 1–11. Because of its good stability and luminescence emission in water, the anionic detections of HNU-35 are evaluated. All results show HNU-35 is a highly selective luminescent sensing material for the detection of Cr(VI) and Mn(VII) in aqueous solution, and the detection limits of Cr2O72–, CrO42–, and MnO4– are 26.46 nM, 20.91 nM, and 13.56 nM. HNU-35 also shows good detection effect in the water samples of the lake and sea, which indicate HNU-35 can serve as a potential sensor for Cr(VI) and Mn(VII) detection.