Solution combustion method to synthesize magnetic Fe3O4 as photocatalytic of Congo red dye and antibacterial activity

Abstract

Abstract Fe3O4 has been synthesized using the combustion solution method using glycine as fuel. The Fe3O4 was used as a catalyst in the photocatalytic degradation of Congo red dye. The Fe3O4 were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS), UV-Vis spectroscopy, and vibrating sample magnetometry (VSM). The characterization showed that Fe3O4 has an inverse spinel structure with a crystalline size of 35.6 nm. Fe3O4 has an optical band gap of 2.16 eV, and a saturation magnetization of 83.76 emu/g. The study showed that the highest photocatalytic degradation was at 90 min of irradiation time using visible light irradiation, the concentration of Congo red dye of 10 mg/L, and pH solution of 5, with a photocatalytic degradation efficiency of 97.70%. The experiment indicated that the photocatalytic degradation of the Congo red dye by Fe3O4 followed a pseudo-first-order. Fe3O4 is effective as an antibacterial against gram-positive bacteria (Streptococcus aureus) and gram-negative bacteria (Escherichia coli).