Abstract:
A series of microporous organic polymers (MOPs) were synthesized by a one-step oxidative coupling reaction using carbazole-functionalized siloles, such as 1,1-dimethyl-3,4-diphenyl-2,5-bis(4'-(9H-carbazol-9-yl)-phenyl)silole, 1-methyl-1-phenyl-3,4-diphenyl-2,5-bis(4'-(9H-carbazol-9-yl)-phenyl)silole and 1,1-diphenyl-3,4-diphenyl-2,5-bis(4'-(9H-carbazol-9-yl)-phenyl)silole. The structure and properties of the three MOPs were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), thermogravimetric (TG) analysis, field emission scanning electron microscope(FSEM) and transmission electron microscope (TEM). FT-IR spectra indicated the success of the oxidative coupling reaction for constructing the polymer frameworks. XRD measurements revealed that all the polymer frameworks were amorphous solid in nature. These MOPs exhibited high thermal stability with the onset of decomposition temperature above 400 ℃ at 5% mass loss under nitrogen flow. The nitrogen adsorption test showed that the specific surface area of the polymers ranged from 587 m
2/g to 617 m
2/g. There was a rigid main chain and nitrogen-rich conjugate structure of microporous skeleton material. The CO
2 adsorption of CPDM-CzS was 2.1 mmol/g (113 kPa, 273 K) and the H
2 adsorption of CPPM-CzS was 0.0151 g/g (113 kPa, 77 K). In addition, CPDM-CzS showed excellent selectivity of adsorption performance of 75.2 for CO
2/N
2. These microporous frameworks will have prospective applications in gas adsorption and separation.