Fabrication of novel magnetic Mg_0.8Cu_0.2Fe₂O₄/SiO₂/CeO₂ nanocomposite synthesized by a simple ultrasonic-assisted route for organic dye removal using Fenton-like reaction

Fenton-like degradation of contaminants is considered to be a feasible method for eliminating environmental pollution. In this study, a novel ternary Mg_0.8Cu_0.2Fe₂O₄/SiO₂/CeO₂ nanocomposite was fabricated using a novel ultrasonic-assisted technique, and investigated as a Fenton-like catalyst for the removal of tartrazine (TRZ) dye. The nanocomposite was synthesized by first coating the SiO₂ shell around the Mg_0.8Cu_0.2Fe₂O₄ core via a Stöber-like process to form Mg_0.8Cu_0.2Fe₂O₄/SiO₂. Then, a simple ultrasonic-assisted route was used to synthesize Mg_0.8Cu_0.2Fe₂O₄/SiO₂/CeO₂ nanocomposite. This approach provides a simple and environmentally friendly way to produce this material without the use of any additional reductants or organic surfactants. The fabricated sample demonstrated excellent Fenton-like activity. The efficiency of Mg_0.8Cu_0.2Fe₂O₄ was significantly enhanced by the incorporation of SiO₂ and CeO₂, and complete removal of TRZ (30 mg/L) was achieved within 120 min using 0.2 g/L of Mg_0.8Cu_0.2Fe₂O₄/SiO₂/CeO₂. The scavenger test shows that the main active species is the strong oxidizing of hydroxyl radicals (HO^•). Consequently, the Fenton-like mechanism of Mg_0.8Cu_0.2Fe₂O₄/SiO₂/CeO₂ is explained based on the coexistence of Fe³⁺/Fe²⁺, Cu²⁺/Cu⁺, and Ce⁴⁺/Ce³⁺ redox couples. The removal efficiency of TRZ dye remained around 85% after the third recycling run, revealing that the nanocomposite could be employed to eliminate organic contaminants in water treatment. This research opened up a new avenue for expanding the practical application of new-generation Fenton-like catalysts.