Construction Of Organic-inorganic Hybrid Nanomaterials And Study Of Tetracycline Detection And Degradation

Organic-inorganic hybrid nanomaterials are widely used in the field of real-time detection and pollution control of tetracycline residues in the environment because of their adjustable structure,easy functionalization modification and strong anti-interference ability.In this thesis,we have prepared fluorescent composites and magnetic catalytic materials for the detection and degradation of tetracycline using chalcogenide with good luminescence properties and covalent organic frameworks with large specific surface area as matrix materials,combined with rare earth organic complexes and metal nanoparticles,respectively.The study is mainly divided into the following parts:（1）In this study,core-shell chalcogenide nanocrystals（Cs Pb Br₃@Cs₄Pb Br₆）with green fluorescence were synthesized by precipitation method,and their surfaces were modified with amination（-NH₂）by silylation reaction,and grafted with citrate rare-earth europium complex（Cit-Eu）by subsequent covalent interaction to constitute multicolor ratiometric fluorescent nanoprobes of tetracycline（TC）probes.The fluorescent nanoprobe has good detection sensitivity with a detection limit as low as12.1 n M.And a logic gate switch based on the fluorescent color variable design has been developed to realize the intelligent visual monitoring of tetracycline.（2）A water-stable halide perovskite（MAPbBr₃@PbBr（OH））was prepared as a host material and coated with a layer of silicon dioxide（Si O₂）by surface modification,utilizing the abundant amino groups on its surface.The functional group realizes the loading of rare earth europium complex（Cit-Eu）,and constructs a highly sensitive visual multicolor fluorescence sensor for the detection of tetracycline（TC）in water and actual samples,with a detection limit as low as 11.15 n M.In addition,paper-based and glove-enabled portable fluorescence sensors were developed with the assistance of a color scanning application in a smartphone,enabling rapid semi-quantitative and qualitative analysis of tetracycline residues on the surface of various fruits and vegetables.（3）A hybrid Fenton nanocatalyst（COF@Fe₃O₄@Au）for the efficient catalytic degradation of tetracycline（TC）was prepared by loading magnetic triiron tetroxide（Fe₃O₄）and gold（Au）nanoparticles on the surface of covalent organic framework nanomaterials（COFs）as carriers through hydrothermal and reduction reactions.The catalyst exhibited excellent catalytic oxidation performance for TC,and the degradation efficiency of TC could reach 94.45%within 100 min.In addition,the catalytic cycling experiments demonstrated the good stability and recyclability of the prepared catalyst.