Comparing the Degradation Potential of Copper(II), Iron(II), Iron(III) Oxides, and Their Composite Nanoparticles in a Heterogeneous Photo-Fenton System

Heterogeneous photo-Fenton systems offer efficient solutions for the treatment of wastewaters in the textile industry. This study investigated the fabrication and structural characterization of novel peculiar-shaped (CuO)-O-II, (Fe2O3)-O-III, and (FeO)-O-II nanoparticles (NPs) compared to the properties of the iron(II)-doped copper ferrite (Cu0.4Fe0.6Fe2O4)-Fe-II-Fe-II-O-III. The photocatalytic efficiencies of these NPs and the composite of the simple oxides ((CuO)-O-II/(FeO)-O-II/(Fe2O3)-O-III) regarding the degradation of methylene blue (MB) and rhodamine B (RhB) as model dyes were also determined. The catalysts were synthesized via simple co-precipitation and calcination technique. X-ray diffractometry (XRD), scanning electron microscopy (SEM), and diffuse reflectance spectroscopy (DRS) were utilized for structural characterization. The structure of (CuO)-O-II was bead-like connected into threads, (Fe2O3)-O-III was rod-like, while (FeO)-O-II pallet-like, with average crystallite sizes of 18.9, 36.9, and 37.1 nm, respectively. The highest degradation efficiency was achieved by (CuO)-O-II for RhB and by (Cu0.4Fe0.6Fe2O4)-Fe-II-Fe-II-O-III for MB. The (CuO)-O-II/(FeO)-O-II/(Fe2O3)-O-III composite proved to be the second-best catalyst in both cases, with excellent reusability. Hence, these NPs can be successfully applied as heterogeneous photo-Fenton catalysts for the removal of hazardous pollutants. Moreover, the simple metal oxides and the iron(II)-doped copper ferrite displayed a sufficient antibacterial activity against Gram-negative Vibrio fischeri.

Automated summary

This study investigated the fabrication and structural characterization of novel peculiar-shaped nanoparticles, as well as their photocatalytic efficiency for dye degradation. The results showed that (CuO)-O-II and (Cu0.4Fe0.6Fe2O4)-Fe-II-Fe-II-O-III exhibited high catalytic efficiency, while the composite (CuO)-O-II/(FeO)-O-II/(Fe2O3)-O-III showed good reusability.