Preparation Of Novel Porous Materials And Their Applications In Fluorescence Sensing And Iodine Adsorption

In recent years,the development of porous materials is relatively rapid,there are many different types.New porous organic materials can be used in gas adsorption and storage,chemical sensing,separation,energy storage and multiphase catalysis due to their various functions,easy synthesis and easy structure modification.Among porous materials,macromolecular materials are often used as fluorescence sensors and I₂ adsorbent due to their simple preparation and high sensitivity.Porous organic polymer（POPs）and porous inorganic-organic hybrid polymers（PHPs）have attracted more and more attention in the field of chemical sensing and iodine adsorption due to their stable physical and chemical properties,high specific surface areas,open pore structures,low density and many synthesis methods.In this paper,4 POPs and 1 PHPs were designed and synthesized through Friedel-Crafts reactions,and their applications in fluorescence sensing and iodine adsorption were investigated.（1）Two CTFs（TTPATTh and TTPATCz）were synthesized successfully,and the multifunctional thiophenyl covalent triazine skeleton（TTPATTh）with trianiline as the core was synthesized for the first time.The yield of TTPATTh（99.59%）was much higher than that of carbazoly-based CTF（TTPATCz,47.03%）.TTPATTh and TTPATCz have high BET specific surface areas(1235 and 2501 m² g^-1,respectively)and large pore volumes(1.60 and2.23 cm³ g^-1)respectively.With the introduction of triazine ring,the fluorescence sensing sensitivity of TTPATTh and TTPATCz to PA and iodine was increased significantly.The detection limits of TTPATTh for PA and iodine were 1.02×10^-12 and 1.86×10^-12 mol L^-1,respectively.The detection limits of TTPATCz for PA and iodine were 3.32×10^-11 and3.87×10^-11 mol L^-1,respectively.Both CTFs have good adsorption capacity for iodine,and the adsorption capacity of TTPATTh and TTPATCz can reach 2.58 and 3.82 g g^-1;（2）Two nitrogenous CMPs（TEDOT and TBTh）have been successfully synthesized,introducing thiophene units into these two CMPs,and the rigid conjugated framework of thiophene contributes to the formation of porous polymers with high stability and porosity.The yield of TEDOT and TBTh were 80.83%and 75.83%,respectively.Due to the presence of heteroatoms（nitrogen or sulfur）in the structure,the two MPS are electron-rich,enhancing the interaction between the CMP networks and the analyte.Therefore,these two CMPs have good fluorescence detection ability of 2,4-dinitrophenol（DNP）.The detection limits of DNP by TEDOT and TBTh were 1.59×10^-13 and 1.38×10^-10 mol L^-1,respectively.Both CMPs showed certain iodine adsorption capacity.（3）A novel nitrogen-rich PHPs（TMPS）with yield of 84.83%was synthesized.It has good sensitivity to nitro-aromatic compounds.The BET specific surface area was 45 m² g^-1 by nitrogen adsorption desorption experiment.TMPS showed very high sensitivity and selectivity to DNP due to its excellent conjugate structure and nitrogen rich characteristics.Based on the data obtained from the fluorescence detection experiment,the detection limits were calculated to be 16.3 ppb L^-1.Therefore,TMPS can be used as a fast and sensitive fluorescence sensor for DNP detection.