Construction of an Aminated MIL-53(Al)-Functionalized Carbon Nanotube for the Efficient Removal of Bisphenol AF and Metribuzin

A versatile organic–inorganic hybrid structure makes a metal–organic framework (MOF) an outstanding host for different kinds of guests; in addition, its easy pyrolysis nature has been proven to be useful as precursors in the construction of carbon-based materials with a special porous structure. Herein, a novel porous composite nanostructure of an aminated MIL-53­(Al)@carbon nanotube (CNT) has been successfully constructed for the first time based on in situ synthesis combining the pyrolysis of ZIF-67. The resulting composite nanostructure was performed by the means of scanning electron microscopy, Brunauer–Emmett–Teller analysis, typical and high-resolution transmission electronic microscopy, X-ray photoelectron spectroscopy, etc. The results showed that a compact heterostructure has been formed between an aminated MIL-53­(Al) and a CNT. The resulting composites, named N-MIL@CNT, represent distinct promoted activities in the removal of Bisphenol AF (BPAF) and Metribuzin from wastewater, and the maximum adsorption values were 274 mg/g (BPAF) and 213 mg/g (Metribuzin), which are larger than the results obtained by other MOF-based nanomaterials. The adsorption isotherm, kinetics, and thermodynamics were studied in detail, and the selective adsorption mechanism was also suggested. The excellent selectivity, reusability, and structure stability suggest the potential application of this composite nanostructure in the selective removal of BPAF or Metribuzin from the practical wastewater.