Design and synthesis of covalent organic framework and its characterization

Abstract

Porous crystalline materials are one of the emerging and most promising branch of material chemistry, comprising of zeolites, metal organic frameworks, covalent organic frameworks and porous organic cages. The use of crystalline porous networks like Covalent Organic Framework (COF) have attracted enormous attention due to their porosity, tunable nature, chemical stability, long-range order, large surface area, high thermal and chemical stability, electronic interactions, charge carrier transport, efficient photocatalytic activity, tunable band gap, visible light absorbance and most important cost effectiveness etc. among widely studied porous polymers, Covalent Amide Framework (CAF) a type of COF with long-range order, isoreticular network structure containing strong bonds, exhibiting irreversibility of the network produced and producing locked-in disorder. In work submitted, we have shown the synthesis of CAF using high pressure and high-temperature reaction conditions. Such conditions have proved their beneficiary mark on the generation of crystallinity in the amorphous locked-in network created. Further characterization shows the effect of reaction conditions utilized, and a comparative study leads to the generation of an optimized path for the above. The aforementioned material was synthesized by reaction of melamine with freshly prepared trimesoyl chloride in the presence of DMF, after which the solvent was removed and the material obtained was subjected to mechanical grinding. The material obtained subjected to different conditions of temperature and solvent amount done in an ampule sealed at low-pressure condition in the presence of liquid nitrogen to create desired isoreticular network.