Ternary Fe3O4-CeO2/g-C3N4 nanocomposite: A magnetically reclaimable, visible light-active catalyst for efficient degradation of bisphenol A

This study reports the fabrication of magnetically recyclable visible light active Fe₃O₄-CeO₂/g-C₃N₄ nanocomposite via simple hydrothermal method. The fabricated nanocomposite showed an excellent photocatalytic activity on the degradation of organic micropollutant such as bisphenol A (BPA) under direct sunlight. Various characterization techniques revealed the formation of the Fe₃O₄-CeO₂/g-C₃N₄ nanocomposite. Furthermore, from the optical study it revealed that the band gap energy for Fe₃O₄-CeO₂/g-C₃N₄ nanocomposite was 1.9 eV. Hence, this small band gap energy depicts the capability of harvesting visible light which makes it favorable for photocatalytic activity under direct sunlight. In addition, the fabricated Fe₃O₄-CeO₂/g-C₃N₄ nanocomposite exhibits a surface area of 148.53 m²/g that is relatively greater than that of CeO₂ and Fe₃O₄ NPs (43.63 m²/g and 79.88 m²/g respectively). It has been studied that 5.0 mg of catalyst could efficiently degrade a maximum of 92.5 ± 1.2 % of 3.0 mg/L solution of BPA in 75 min under direct sunlight. The charge transfer among all three components of the prepared Fe₃O₄-CeO₂/g-C₃N₄ nanocomposite resulted in an increase in activity of the photocatalyst as the longevity of the charge carrier was increased by preventing its fast recombination. The kinetic study showed relatively high-rate constant of 3.9 × 10⁻² min⁻¹, hence the photodegradation reaction follows pseudo-first-order mechanism. The catalyst was effortlessly recovered magnetically and reused up to 7th cycles of photodegradation of BPA. Therefore, this study reveals the successful accomplishment of fabrication of magnetically recyclable visible light active Fe₃O₄-CeO₂/g-C₃N₄ nanocomposite which exhibits high photocatalytic efficiency on the degradation of BPA under direct sunlight.