Fe doped carbon/COFs electro-spinning nanofiber for selective adsorption and photocatalytic degradation on dye pollutant by confining effect in treatment of water

In this study, a novel Fe doped carbon/COF nanofibrous membrane was prepared for selective adsorption and efficiently photocatalytic degradation on dyes. The Fe doped carbon nanofiber was obtained from electron-spinning polyacrylonitrile/sodium alginate/MIL-88 A nanofiber following with a carbonization procedure. Subsequently, the covalent triazine frameworks (CTFs) were formed in situ on the carbon nanofiber to prepare the novel Fe-doped carbon/covalent triazine frameworks (C/Fe@CTFs). The C/Fe@CTFs membrane exhibits selective adsorption on malachite green (MG) due to the confining effect of the CTFs. The adsorption experiments reveal that pseudo-second-order kinetics and Langmuir isotherm model fit better to the real process on MG adsorption, and DFT calculation is utilized to investigate the affinity between absorbent and adsorbate by determining the electron density and molecular orbital of each sample. Moreover, the C/Fe@CTFs presents improved photocatalytic effect against MG with a removal rate of 93.6 % with promoted service life under simulated sunlight irradiation. In brief, the C/Fe@CTFs membrane displays selectively adsorbing, efficiently photo-catalysing, improved bacteria inhibiting is a promising candidate for practical application on dye pollutant removal in water treatment. • Fe-doped carbon nanofibrous membrane was developed for selective adsorption and efficiently photocatalytic degradation of dyes. • The confinement effect of the carbon nanofibrous membrane was analyzed by DFT calculation. • The photo-catalytic mechanism and degradation pathway were explored on MG.