A facile preparation of ZnFe₂O₄–CuO-N/B/RGO and ZnFe₂O₄–CuO–C₃N₄ ternary heterojunction nanophotocatalyst: characterization, biocompatibility, photo-Fenton-like degradation of MO and magnetic properties

Abstract

To improve the low photocatalytic efficiency, powerful UV light activation, and facile electron transport of ZnFe₂O₄–CuO the combination of different C₃N₄ and N/B/RGO nanosheets in ZnFe₂O₄–CuO–C₃N₄ and ZnFe₂O₄–CuO-N/B/RGO ternary nanoheterojunction fabricated that lead to decrease recombination of electron/hole pairs and high photocatalytic efficiency for degradation of MO organic pollutants. The ZnFe₂O₄, ZnFe₂O₄-N/B/RGO, CuO-N/B/RGO, ZnFe₂O_4–CuO, ZnFe₂O₄–CuO-N/RGO, ZnFe₂O₄–CuO-B/RGO, ZnFe₂O₄–CuO-RGO, ZnFe₂O₄–CuO-N/B/RGO and ZnFe₂O₄–CuO–C₃N₄ photocatalysts were fabricated by sol–gel technique using melamine, zinc nitrate, ferric nitrate and copper nitrate hexahydrate as precursors. The prepared ZnFe₂O₄–CuO–C₃N₄ photocatalysts have a narrower bandgap than that of ZnFe₂O₄–CuO-N/B/RGO ternary heterojunction, resulting in higher photocatalytic activity for Fenton-type photodecomposition of methyl orange (MO). The activity of the compounds as a photocatalyst can be attributed to an electron transfer process on the surface of the photocatalyst, where the ZnFe₂O₄–CuO–C₃N₄ is a powerful electron donor and electron acceptor for the oxidized MO under ultra-violet (UV) light irradiation. ZnFe₂O₄–CuO–C₃N₄ ternary heterojunction photocatalyst show a red shift (lowest bandgap) in absorption and excellent photocatalytic degradation of MO. The particle sizes of ZnFe₂O₄ and CuO nanoparticles (NPs) were in the ranges of ~ 650–750 and ~ 50–150 nm, respectively. The CuO and ZnFe₂O₄ samples were displayed spherical and cubic morphology in FESEM images, respectively. Among the as-prepared nanostructures ZnFe₂O₄–CuO–C₃N₄ show the highest photocatalytic activity and eliminate 95.84% (80 min) of methyl orange under UV light irradiation.