Electrospun CuO–Fe₃O₄ Tube Catalyst for the Decomposition of Organic Matter via an Accelerated Heterogeneous Fenton-like Process

Abstract

The Fenton reaction plays a fundamental role in advanced oxidation processes for the degradation of organic pollutants. Here, we report the high activity and durability of the CuO–Fe3O4 tube catalyst in the decomposition of organic matter via a heterogeneous Fenton-like process. The catalytic activity of the prepared catalysts is evaluated by the degradation of commonly used organic dyes, methylene blue (MB) and methyl orange (MO). The CuO–Fe3O4 tube catalyst is prepared by the electrospinning method, which is capable of large-scale synthesis. The synthesized catalyst is characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS), which confirms a tube-like structure of CuO having an inner wall decorated with Fe3O4. The CuO–Fe3O4 tube catalyst promotes the MB and MO degradation reaction compared with the conventional CuO particle catalyst. The improved degradation rate originates from the (1) high utilization of active sites (Cu­(I) and Fe­(II)) for generating reactive •OH radicals and (2) efficient regeneration of active Fe­(II) by Cu­(I) inside the tube. The SEM analysis after the reaction confirms the high durability of the CuO–Fe3O4 tube catalyst. The unique tube-like structure with the coexistence of CuO and Fe3O4 proves to be a valid strategy to accelerate the heterogeneous Fenton-like process for removing organic pollutants from wastewater.