Magnetic nanocomposites of Fe3C or Ni-substituted (Fe3C/Fe3O4) with carbon for degradation of methylene orange and p-nitrophenol

Abstract We report the structural and catalytic behavior for nanocomposites such as Fe3C/C, Fe3C/Fe3O4/Cand Ni-substituted Fe3C/Fe3O4/C, which were synthesized by sol-gel route followed by calcination at 700 oC in N2 atmosphere. The structural and coexistence of the phases present in the nanocomposite were analyzed by X-ray and electron diffraction. The Mossbauer spectroscopy also supported the above findings. The X-ray photoelectron spectroscopy designated the oxidation states and bonding between the elements present in the composites. Magnetic properties measurements system was carried out to examine the effect of Ni substitution on the magnetic behavior of the nanocomposites. The optical band gaps of the prepared nanomaterials were suitable for photocatalytic activity. Thus, the catalytic activities of these nanocomposites were evaluated during the degradation of methyl orange and p-nitrophenol under Fenton-like and photo-Fenton conditions. The optimum apparent catalytic reaction rate constant for Fe3C/Fe3O4/C with p-nitrophenol and methyl orange were ∼ 1.48 x 10-2 and 3.36 x 10-2 mol-1 L-1 min-1, respectively. The catalysts were stable even after 5th cycles of catalytic experiments, and it was confirmed from their XRD patterns.