Green Synthesized Fe<sub>3</sub>O<sub>4</sub>/rGO Nanocomposite for Photodegradation of Rhodamine B

The research on green synthesized Fe 3 O 4 /rGO nanocomposites for the degradation of rhodamine B waste is important to understand the influence of varying masses of Fe 3 O 4 /rGO nanocomposites on the photocatalytic degradation process of rhodamine B. In this research, characterization was conducted using an X-ray diffractometer, Vibrating Sample Magnetometer, UV-visible spectrophotometer (UV-Vis), and Transmission Electron Microscopy (TEM). The Fe 3 O 4 nanoparticles had a crystallite size of 24.4 nm, whereas the Fe 3 O 4 /rGO 5:5 nanocomposite had a crystallite size of 13.5 nm. The saturation magnetization for Fe 3 O 4 nanoparticles was 55.3 emu/g; the Fe 3 O 4 /rGO 5:5 nanocomposite was 21.7 emu/g. From UV-Vis testing, the band gap energy of Fe 3 O 4 nanoparticles was found to be 2.4 eV with an absorbance peak at 332 nm, while the Fe 3 O 4 /rGO 5:5 nanocomposite had a band gap energy of 2.7 eV with absorbance peaks at 337 nm. TEM characterization revealed that Fe 3 O 4 nanoparticles had an average size of 15.6 ± 4.2 nm, while the Fe 3 O 4 /rGO 5:5 nanocomposite particles were 9.3 ± 2.2 nm in size. Besides the above characterizations, photocatalytic tests were conducted to evaluate the performance of the Fe 3 O 4 /rGO 5:5 nanocomposite in degrading rhodamine B waste. It was tested involving varying concentrations of Fe 3 O 4 /rGO nanocomposite i.e. 0.01 g, 0.03 g, 0.05 g, 0.07 g, and 0.09 g. The results showed that the maximum degradation occurred at a mass of 0.05 g Fe 3 O 4 /rGO 5:5 nanocomposite, achieving a degradation percentage of 98.1%. This research concludes that green synthesized Fe 3 O 4 /rGO nanocomposites have the potential for environmentally friendly degradation of rhodamine B.