Novel magnetically separable g-C3N4/AgBr/Fe3O4 nanocomposites as visible-light-driven photocatalysts with highly enhanced activities

In this study, we report novel magnetically separable g-C3N4/AgBr/Fe3O4 nanocomposites as visible-light-driven photocatalysts. The preparation method was simple, large-scale, and low-temperature and did not require any additives or post preparation treatments. The nanocomposites were characterized using X-ray diffraction, transmission electron microscopy, energy dispersive analysis of X-rays, UV–vis diffuse reflectance spectroscopy, Fourier transform-infrared spectroscopy, thermogravimetric analysis, and vibrating sample magnetometry techniques. Photocatalytic activity of the nanocomposites was investigated by degradation of rhodamine B under visible-light irradiation. The nanocomposite with 4:1 weight ratio of g-C3N4/AgBr to Fe3O4 exhibited superior activity in the degradation reaction. Activity of this nanocomposite was about 5.3 and 5-fold higher than those of g-C3N4, and g-C3N4/Fe3O4, respectively. Moreover, we investigated the influence of refluxing time, calcination temperature, and scavengers of reactive species on the degradation activity. Finally, the photocatalyst was magnetically separated, with high efficiency, from the treated solution after five successive cycles.