Design,Synthesis And Properties Of Two Dimensional Quinone-Based Covalent Organic Frameworks

Covalent organic frameworks(COFs)are a class of crystalline organic porous materials connected by covalent bonding of small organic molecules.Due to their high specific surface area,low density,tunable pores,easy functionalization and variety of linkages and construction units,COFs possess a wide range of applications in many fields such as molecular adsorption and separation,catalysis,energy storage and sensing.With simple structure,benzoquinone is rich in physical and chemical properties and widely used in the fields of sensing,catalysis,molecular switching and chemical energy storage.To date,benzoquinone-based COFs have been reported and own prospects in the field of lithium ion batteries and supercapacitors.However,the corresponding reports are rare and the rich properties of benzoquinone-based COFs remains to be further explored.Therefore,this thesis designed and synthesized a new type of benzoquinone-based COF.Firstly,its structure was exhaustively characterized and its properties were studied by cyclic voltammetry.Then,the potential application in metal ions detection of the benzoquinone-based COF with electrochemical approach was preliminarily studied.The concrete content mainly includes two parts:(1)This thesis firstly reviewed the literature on the design,synthesis and application of COFs and introduced the structure and properties of benzoquinone.Then,the current researches on the benzoquinone in COFs were introduced and research ideas of this thesis was finally proposed.(2)A novel precursor of benzoquinone(2,5-bis(4-formylphenyl)benzoquinone)was designed and synthesized to construct a novel benzoquinone-based COF with another construction units pyrene(1,3,6,8-tetrakis(4-aminophenyl)pyrene).This new COF(QUI-COF)possessed a high specific surface area and a large pore.The structure of QUI-COF was characterized by Fourier infrared,solid-state NMR,nitrogen adsorption,scanning electron microscopy,transmission electron microscopy,thermogravimetric analysis and powder X-ray diffraction.The single pore structure with AA stacking mode was confirmed by model simulation.And the properties of QUI-COF were examined by cyclic voltammetry and the potential application in metal ions detection of the QUI-COF with electrochemical approach was preliminarily studied.