Facile Electrochemical Synthesis of Graphene-Encapsulated Fe<sub>3</sub>O<sub>4</sub> Nanoparticles for Dual Photocatalytic and Electrooxidation of Mb Dye

In this study, we synthesize the nanocomposites of Fe 3 O 4 /graphene using an electrochemical exfoliation followed by thermal treatment. The morphology and bonding structure of the prepared samples have been characterized by scanning electron microscopy (SEM) and X-ray diffractometry (XRD). The photo-characteristic aspects of the prepared samples have been indicated by ultraviolet-visible diffuse reflection spectroscopy (DRS). The photocatalytic performance of Fe 3 O 4 /graphene demonstrated that it is an effective photocatalyst for methylene blue (MB) dye decomposition through illumination by a solar simulator. The results showed that after 10 minutes of electrooxidation/photocatalytic treatment in the presence of 1000 mg/L of the nanocomposite, dye degradation exceeded 70%, compared to only 29% with electrooxidation alone. Furthermore, after 60 minutes, degradation reached over 95% with the nanocomposite, compared to 75% for electrooxidation alone. Different MB concentrations and percentage photocatalyst loadings have been investigated. Furthermore, the results showed that as the amount of catalyst increased, the decomposition of MB enhanced. The results showed that the prepared nanocomposites had good photocatalytic activity towards water splitting and photodecomposition of MB.