Activation of calcium peroxide by graphene oxide-supported iron composite (Fe3O4/rGO) as a synergistic catalyst for perchloroethylene remediation

Nano-magnetite (Fe 3 O 4 ) nanoparticles immobilized on reduced graphene oxide (rGO) were synthesized and used for the first time for activation of calcium peroxide (CaO 2 ) for perchloroethylene (PCE) degradation (0.15 mM). Various analytical techniques such as scanning electron microscope, transmission electron microscope, Brunauer–Emmett–Teller surface characterization, and X-ray diffraction have been applied for the characterization of synthesized Fe 3 O 4 /rGO nanocomposite. These techniques validated successfully synthesized spherical-shaped Fe 3 O 4 supported on rGO with surface areas and particle sizes of 176.32 m 2 /g and 80–120 nm, respectively. The support hindered the accumulation and aggregation of Fe 3 O 4 nanoparticles. Furthermore, the effect of Fe 3 O 4 /rGO and CaO 2 doses experiments were also carried out to optimize the degrading performance. The results showed that 0.15 g/L Fe 3 O 4 /rGO and 2.0 mM CaO 2 were sufficient for practically complete degradation of PCE. No production of hydrogen peroxide at alkaline conditions confirmed the system's suitability in acidic conditions. The scavenger experiments demonstrated that the hydroxyl (OH · ) radical plays a more significant role in the degradation of PCE in the Fe 3 O 4 /rGO–CaO 2 system. The mineralization (85%) and dechlorination (89.3%) further validated the non-toxic intermediate and final product generation. The corrosion and active sites lost lowered the recyclability and stability capacity of the catalyst; roughly 18% PCE degradation was observed after 4th cycle. The Fe 3 O 4 /rGO-activated CaO 2 could be an alternative technique for the remediation of PCE in groundwater.