Sol–gel auto-combustion synthesis and characterization of CeO₂/PbFe₁₂O₁₉/g-C₃N₄ nanocomposites with enhanced visible-light photocatalytic activity

Due to efficient charge separation and strong visible-light absorption, g-C₃N₄-based heterogeneous photocatalyts have sparked significant interest in alleviating energy and environmental crisis. The present study reports CeO₂/PbFe₁₂O₁₉ nanocomposite with photocatalytic properties that has been designed via sol–gel auto-combustion process utilizing different carbohydrate sugars as capping agent and fuel. Also, this investigation developed an ultrasonic-assisted co-precipitation route for the creation of ternary CeO₂/PbFe₁₂O₁₉/g-C₃N₄ nanocomposites with diverse contents of nano-CeO₂/PbFe₁₂O₁₉ to promote activity toward the degradation of malachite green (MG) pollutant under visible light. The results showed that 30 mg of resulting CeO₂/PbFe₁₂O₁₉ nanostructures can achieve 46.68% degradation of MG at 10 mg L⁻¹, while nanocomposites having mass ratio of 1:1 for CeO₂/PbFe₁₂O₁₉: g-C₃N₄ showed 81.50% efficiency after 120 min at similar conditions. Radical scavenging experiments confirmed that •OH and h⁺ play a dominant role in MG degradation by CeO₂/PbFe₁₂O₁₉/g-C₃N₄ nanocomposites. These results highlight the potential application of CeO₂/PbFe₁₂O₁₉/g-C₃N₄ as a promising photocatalyst for removing water-soluble organic pollutants.