Synthesis,Structure And Properties Of Nitrogen-Rich Porous Organic Frameworks

Recently,porous organic frameworks?POFs?have drawn significant attention due to their high specific surface area,low skeleton density,high physical-chemical stability,and versatile synthetic strategies.Introducing N-containing functional groups into porous organic frameworks would endow porous polymers with special functions and properties.In this dissertation,we first prepared a series of azo-linked,triazine-based,and carbazole-based POFs by introducing azo,triazine and carbazole nitrogen-rich functional group into POFs.Then we explored their application in carbon dioxide adsorption and seperation,heterogeneous catalysis,ion sensor and so on.The main contents and results altogether are divided to five parts listed as follows.Firstly,we briefly introduced the synthesis routes,development and application of nitrogen-rich POFs especially their application in CO₂ adsorption and separation and heterocatalysis.The significance of the projects and the main work are also outlined.In the second chapter,an azo-linked porous organic network?Azo-Trip?,in which triptycene was incorporated as a building block,had been prepared via a facile Zn-induced reductive homo-coupling reaction.The Azo-Trip exhibits a BET surface area of 510.4 m2g-1,large carbon dioxide uptake?119.6 mg g-1,10.8 wt% at 273 K and 1 bar?,as well as good CO₂/N₂?38.6?selectivity,which could have wide applications on CO₂ adsorption and separation.The resulting polymer also displays an excellent guest uptake of 238 wt% in iodine vapour and outstanding reversible adsorption of iodine in cyclohexane solution.The removal efficiencies reached to 83.3%.In chapter 3,we synthesized two triazine-based porous polymers CTF-DCPE-1 and CTF-DCPE-2 by ZnCl₂ ionothermal methods using di?4-cyanophenyl?ethyne?DCPE?as the monomer.The porous materials have potential applications on gas uptake especially CTF-DCPE-1.It displays high BET surface areas of 2107.034 cm2g-1,large gas uptake capacity?1.41 wt % H2 at 77 K/1 bar,179 mg/g CO₂ at 273 K/1 bar?as well as high selectivity of CO₂ over N₂?CO₂/N₂ Henry's selectivity: 55 at 273K/1.0 bar?.The triazine-based porous organic frameworks CTF-DCPE-1 can coordinate with active silver cations and further used as heterogeneous catalyst for carboxylation of aromatic acetylene under mild conditions.The heterogeneous catalyst can be reused many times without loss of activity.Meanwhile the reaction are tolerated a wide range of substrates.In chapter 4,two carbazole-based polymers TPM-Cz and BCB-Cz were synthesized via FeCl₃ promoted oxidative polymerization.TPM-Cz,synthesized by tetrahedral monomer TPTCz,exhibits high BET surface areas of 713.158 m2g-1 and good gas uptake capacity?96.3 mg/g at 273K/l bar for CO₂,and 1.34 wt % at 77 K /l bar for H2?respectively.By Combination of porosity and excellent luminescent properties of carbazole group,TPM-Cz can rapidly detect of I-ions and aromatic nitro compounds explosive.In the last chapter,a concise conclusion was drawn and an outlook of this work was expected.