Preparation Of Several Organic Two-dimensional Materials And Their Photocatalytic And Biological Applications

This paper starts with three different connection methods:dynamic reversible covalent bond,covalent bond,and non-covalent bond,and constructs a series of organic two-dimensional materials in the solution and interface and studies their properties and their applications in photocatalysis and biology.The paper is mainly composed of the following parts:In Chapter 1,we summarized the development of two-dimensional materials,the problems they face,and the exploration of applications.In Chapter 2,we synthesize monomeric TFPT based on triazine units.The TFPT and 1,4-benzenediacetonitrile are heated in Pyrex tube by Knoevenagel condensation reaction to obtain 2D COFs with reversibly covalently bonded covalently bonded states.We systematically studied the characteristic groups,micromorphology,crystal structure of triazine COFs by infrared,XRD,scanning electron microscopy,and transmission electron microscopy.Furthermore,the application of this material in photocatalytic coenzyme NADH was studied.Studies have shown that triazine COFs catalyze the regeneration efficiency of coenzyme NADH to reach 90%within 10 minutes,showing excellent catalytic performance.In Chapter 3,Two-dimensional(2D)N-graphdiyne(N-GDY)nanosheets containing different number of N were synthesized by polymerization of triazine,pyrazine,and pyridine-based monomers at liquid/liquid interface.The configurations and nanostructures of N-GDY were well-characterized.The wettability changed to more hydrophilic as the N contents increased.The collected N-GDY was further employed as metal-free photocatalyst for NADH regeneration.The catalytic performance was related with the N content in the graphdiyne.The N3-GDY demonstrated the best activity.This strategy provided a new promising platform of designing unique 2D N-GDY with tunable performance in biorelated catalysis.In Chapter 4,we report a successful combination of supramolecular self-assembly,AIE effect,and DNA staining.A series of water-soluble tritopic molecules containing different cores and styrylpyridium were synthesized.Two different self-assembled modes head-to-tail and head-to-head with CB[8]lead to formations of two-dimensional supramolecular organic frameworks(SOFs)or dimers.This was evidenced by ~1H-NMR,DLS and Cryo-TEM.Obvious aggregation-induced emission(AIE)phenomenon was observed for the Two-dimensional supramolecular assemblies and were successfully used to stain DNA.