Facile preparation of magnetic composites based on carbon nanotubes: Utilization for removal of environmental...

The preparation of multifunctional composites that combine magnetic nanoparticles and supported nanomaterials has attracted great attention for various applications. In this work, a facile method was developed for the preparation of carbon nanotube (CNT)-based magnetic composites through a one-pot oxidation method using K₂FeO₄ as the oxidant, which was subsequently used as the reagent to generate the Fe₃O₄ nanoparticles and fabricate the magnetic CNT composites. This strategy could be performed at room temperature, so it is very mild and straightforward. The properties and structure of the as-fabricated CNT-Fe₃O₄ composites were characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, and vibrating sample magnetometry. The results suggested that this approach not only generated Fe₃O₄ magnetic nanoparticles on the surface of the CNTs but also produced a series of functional groups. In addition, the dried CNT-Fe₃O₄ composites were highly dispersible in water or organic solutions, and they also had a magnetic response that could satisfy the demand for magnetic separation. Finally, we adsorbed copper ions (Cu²⁺) and methylene blue (MB) using the CNT-Fe₃O₄ composites as adsorbents. The results indicated that the obtained composites could adsorb both Cu²⁺ and MB effectively. Taken together, we report a novel strategy for the fabrication of magnetic carbon nanotube composites through a facile oxidation and subsequent deposition procedure. These magnetic composites show great potential for the removal of environmental pollutants.