One-pot synthesis of two novel Ce-MOFs for the detection of tetracyclic antibiotics and Fe3+

In this article, two novel Ce-MOFs were prepared by hexacarboxylic acid and Ce(NO3)3·6H2O with the hydrothermal method, while the yellow cubic structure is named MOF-1 and the colorless transparent strip structure is named MOF-2. The physicochemical properties of the two MOFs were characterized by FTIR, TG, DSC, BET, SEM, EDS etc. Both MOFs are composed of four elements: C, H, O, N, and Ce. Single crystal X-ray diffraction showed that MOF-1 belongs to trigonal system, R-3 space group, and it presents a three-dimensional structure. The specific surface area of MOF-1 was 13.461 m2/g with an average pore radius of 14.23 nm and that of MOF-2 was 2.5669 m2/g with an average pore radius of 8.91 nm. In addition, the fluorescence sensing performance of the two MOFs were also tested. MOF-1 and MOF-2 showed good sensing properties for tetracycline antibiotics and Fe3+ ions, respectively. Both MOFs exhibited a wide detection range and low detection limit, such as the detection range of MOF-2 for Fe3+ is 40-180 μM, and the detection limit is 0.01 nM. The sensing mechanism of the two MOFs can be explained by FRET and competitive absorption. These two MOFs have great application prospects in the fields of antibiotics and industrial wastewater detection due to their good water stability and sensing performance.