Eco-friendly TiO2-doped Fe3O4/rGO nanocomposites synthesized using plant extracts for photodegradation of organic dye

• Eco-friendly Fe 3 O 4 /rGO/TiO 2 nanocomposites were synthesized utilizing Moringa oleifera and Amaranthus viridis . • Green-synthesized Fe 3 O 4 /rGO/TiO 2 nanocomposites have strong magnetic properties. • Green-synthesized Fe 3 O 4 /rGO/TiO 2 nanocomposites have superior photocatalytic activity up to 99% for 20 minutes. • Green-synthesized Fe 3 O 4 /rGO/TiO 2 nanocomposites were easily separated making them suitable for multiple reuse cycles. This study focused on green-synthesized titanium dioxide-doped magnetite/reduced graphene oxide nanocomposites (TiO 2 -doped Fe 3 O 4 /rGO) using Moringa oleifera (MO) and Amaranthus viridis (AV) leaf extracts for degradation of methylene blue (MB) dye. TiO 2 is a widely used photocatalyst but suffers from rapid electron–hole recombination and limited reusability. Therefore, TiO 2 was combined with rGO and Fe 3 O 4 ; rGO improves charge separation, while Fe 3 O 4 enhances electron transport and enables magnetic recovery. The nanocomposites are prepared by coprecipitation methods with various concentrations to obtain efficient photocatalytic degradation. The existence of TiO 2 -doped Fe 3 O 4 /rGO was proved by phase composition from X-ray diffraction, selected area electron diffraction, and binding from Fourier-transform infrared spectra. The stretching vibration peaks for C-H and C=C bonds indicate the successful preparation of green-synthesized nanoparticles using MO and AV extracts. Phenolics and flavonoids act as natural reducing agents by donating electrons to metal ions, facilitating their reduction to elemental metal nanoparticles. TiO 2 and Fe 3 O 4 nanoparticles are distributed on the rGO sheet. rGO facilitates efficient electron transfer and suppresses electron-hole recombination. The molar ratio of titanium has a significant effect on the photocatalytic activity of MB, and nanocomposites can remove 99 % of MB from an aqueous solution in 20 min. According to vibrating sample magnetometer analysis and cycle experiments, TiO 2 -doped Fe 3 O 4 /rGO photocatalyst maintained superior magnetism, stability and recycling performance. The degradation ability of nanocomposites was reduced by just 2.2 % after three cycles. The TiO 2 -doped Fe 3 O 4 /rGO nanocomposite could potentially be used as an economical, environmentally friendly, and reusable photocatalyst for removing organic pollutants from wastewater.