Interface engineering of a magnetic 2D-C3N4/Fe2O3/NiFe-LDH heterostructure for efficient photocatalytic degradation of methylene blue and rhodamine B dyes under visible light

Double layer hydroxide (LDH) as a photocatalyst has potential features in water pollution control. In the present study, the iron (III) oxide /two-dimensional carbon nitride/nickel-iron LDH (Fe2O3/2D-C3N4/NiFe-LDH) composite was synthesized by pyrolysis and co-precipitation process from waste iron rusts as one of the cheap precursors along with NiFe-LDH and g-C3N4. The photocatalytic activities of magnetic Fe2O3/2D-C3N4/NiFe-LDH as stable photocatalyst for degradation of methylene blue (MB) and rhodamine B (RhB) as cationic dyes was studied and then the characteristics of the resulting materials, including morphology, structure, crystal phase, optical and electronic properties, were clearly investigated using different techniques. The fabricated Fe2O3/2D-C3N4/NiFe-LDH provide greatly improved photocatalytic performance for dye degradation compared to the sole Fe2O3 and Fe2O3/g-C3N4.The maximum elimination efficiency of MB and RhB are 91.2% and 88.5% respectively. 80% COD photodegradation was achieved under optimal conditions including catalyst loading (0.36 g/L), initial pH (9.0), LED irradiation time (60 min), and initial concentration of MB (10 mg/L) and RhB (9 mg/L). The obtained photocatalyst was effectively recovered using an applied magnetic field. Based on the reusability study, the fabricated photocatalyst was chemically stable and corrosion resistant.

Automated summary

In this study, an Fe2O3/2D-C3N4/NiFe-LDH composite was successfully synthesized from waste iron rusts using pyrolysis and co-precipitation methods and investigated as a stable photocatalyst for the degradation of cationic dyes. The results showed that the fabricated composite exhibited enhanced photocatalytic performance compared to pure Fe2O3 and Fe2O3/g-C3N4. The maximum elimination efficiencies of MB and RhB were 91.2% and 88.5% respectively. The photocatalyst could be efficiently recovered using an applied magnetic field and was found to be chemically stable and corrosion resistant.