Photocatalytic degradation of Congo red dye using N and S doped rGO / NiFe 2 O 4 heterogeneous nanocomposite under visible light

Abstract BACKGROUND This study reports the design and fabrication of a series of heterogeneous N,S‐rGO/NiFe 2 O 4 ‐X% nanocomposites, where X represents the weight percentage of NiFe 2 O 4 . Nitrogen and sulfur dopants were deliberately introduced into the graphene oxide framework, followed by the concurrent anchoring of NiFe 2 O 4 nanoparticles within the graphene oxide layers through a controlled hydrothermal approach. The structure, morphology, optical characteristics, and photocatalytic activity of the nanocomposites were precisely characterized using XRD, XPS, FTIR, Raman spectroscopy, FESEM, TEM, EDAX, elemental mapping, DRS, BET, PL, and EIS, which collectively validated the successful integration of the designed components. RESULTS The results confirmed the effective reduction of graphene oxide and the successful incorporation of NiFe 2 O 4 nanoparticles between the reduced graphene oxide layers. For the first time, the photocatalytic activity of these engineered nanocomposites was exclusively evaluated for the chemical degradation of Congo red dye, selected as a model organic pollutant, under visible irradiation, yielding successful outcomes. CONCLUSION Our study demonstrated the outstanding photocatalytic activity of the N,S‐rGO/NiFe 2 O 4 heterostructured nanocomposite. Among the prepared samples, the N,S‐rGO/NiFe 2 O 4 –30% nanocomposite demonstrated an outstanding degradation efficiency of 91.45% for a 10 mg/L solution within 1 h under visible‐light irradiation. Furthermore, the material exhibited remarkable structural stability and reusability, maintaining its catalytic performance without any measurable loss in activity or mass even after 12 consecutive cycles. These findings establish the novelty of this research work and highlight the significant potential of the synthesized N,S‐rGO/NiFe 2 O 4 nanocomposites as durable and recyclable photocatalysts for environmental remediation applications. © 2026 Society of Chemical Industry (SCI).