Ag-doped FeCo2O4 nanoparticles and their composite with flat 2D reduced graphene oxide sheets for photocatalytic degradation of colored and colorless compounds

The present study is based on the fabrication of nanoparticles of iron cobalt oxide (FeCo2O4, FCO), silver doped iron cobalt oxide (Ag-FeCo2O4, AgFCO) by auto-moisturization approach. The nanocomposite of silver doped iron cobalt oxide with reduced graphene oxide (Ag-FeCo2O4@rGO, AgFCO@rGO) was fabricated by ultra-sonication approach for the degradation of the organic effluents photocatalytically. The rGO possesses immense surface area, excellent stability, and greater ability for the transfer of electrons during photocatalysis. The physiochemical characteristics of fabricated materials were investigated by X-ray diffraction technique (XRD), Fourier transform infrared spectroscopic technique (FT-IR), Scanning electron microscopy (SEM), and UV - Visible spectroscopy. The results of XRD showed that the crystallite size of FCO, AgFCO, and AgFCO@rGO nanocomposite was 14 nm, 12 nm, and 10 nm respectively. The results of SEM revealed quasi spherical morphology of synthesized materials and rGO sheets could be easily observed in the SEM image of AgFCO@rGO. The degradation of rhodamine B and benzimidazole was performed under solar light. The photocatalysis experiment exhibited 86 % degradation of rhodamine B and 54.46 % degradation of benzimidazole by using AgFCO@rGO under the same conditions. The photoactive species like hydroxyl radicals, holes and electrons were found to be main participants during photo-degradation of pollutants. In contrast to bare iron cobalt oxide and silver doped iron cobalt oxide, AgFCO@rGO showed greater photocatalytic degradation activity. The increased activity of AgFCO@rGO was due to its small crystallite size and increased surface area. The recombining rate of electron/hole pair decreased as the surface area of nanocatalysts increased and hence photocatalytic efficiency increased. It is investigated that the AgFCO@rGO has potential implementations in the photo degradation of organic effluents.