A novel Zn MOFs as a multifunctional sensitive chemical sensor for the rapid detection of nitroaromatic compounds, Tetracycline, Fe3+, and degradation for methyl orange

The rapid detection of pollutants in the environment is of great significance. In this work, a novel MOF, namely [Zn(TPPA)(L)]_n (1) has been synthesized based on a π-electron rich triangular ligand TPPA (TPPA=tris(4-(pyridin-4-yl)phenyl)amine and H₂L=2,3-dihydrothieno[3,4-b][1,4]dioxine-5,7-dicarboxylic acid). Compound 1 is a 3-fold interpenetrating (3,5)-connected 3D framework. Photoluminescence studies indicate that the emission of 1 result from the charge transfer transition between ligands (π → π*). 1 with excellent luminous performance can be applied as a multi-functional chemical sensor for nitroaromatic compounds (NACs), toxic metal ions and antibiotics, and quick response. In addition, 1 exhibits photocatalytic activity for the degradation of methyl orange (MO) in the visible regions and is stable during the photocatalysis process. The effective detection of NACs and antibiotics was rationalized by density functional theory (DFT) calculation of the energy bands of NACs and antibiotics, which revealed that photoinduced electron transfer (PET) mechanism is largely responsible for the sensing of NACs. PET mechanism and resonance energy transfer play significant roles in the exclusive sensing of tetracycline hydrochloride (TCH).