Photodegradation enhancement of organic dyes using magnetically separable and reusable Fe3O4/rGO nanocomposites green-synthesized utilizing plant leaves extract

This study aims to investigate the facile fabrication of Fe 3 O 4 /rGO nanocomposites based on the green synthesis method, utilizing Moringa oleifera and Amaranthus viridis extracts for photocatalytic degradation application. The coprecipitation and modified Hummer methods were used to synthesize Fe 3 O 4 and rGO, respectively. Both materials were stirred to connect Fe 3 O 4 on the surface of the rGO sheet to produce a nanocomposite. The nanocomposites as a photocatalyst were characterized to investigate the structural, bonding, optical, and magnetic properties. The X-ray diffraction spectrum of Fe 3 O 4 /rGO nanocomposites is cubic inverse spinel with a crystalline size around 10 nm. The transmission electron microscope results show a decrease in particle size of Fe 3 O 4 /rGO with the addition of rGO. Fe–O functional groups in the nanocomposite show the presence of Fe 3 O 4 on the rGO surface. The addition of rGO concentration affects the saturation magnetization and coercivity values of the nanocomposites. Meanwhile, the methylene blue degradation efficiency is optimal for Fe 3 O 4 /rGO nanocomposites at a concentration of 5:5, reaching 99.3 % degradation during a 3-h photocatalytic process. The magnetic potential of Fe 3 O 4 /rGO nanocomposites means that the photocatalyst can be recycled up to three times with a high degradation rate. Therefore, the Fe 3 O 4 /rGO nanocomposite has the potential as a reusable, environmentally friendly, and cost-effective photocatalyst for the removal of organic pollutants from wastewater.