A novel magnetically separable N doped ZnO/SiO2/Fe3O4 photocatalyst for degradation of Congo red under visible light

N-doped ZnO/SiO2/Fe3O4 as a new magnetic photocatalyst that is active in visible light have been prepared by simple so-gel method. The prepared samples were characterized by XRD, TEM and, VSM analysis. The photocatalytic effect of synthesized samples on Congo red degradation was studied. Experimental condition including pH, irradiation time, Congo red concentration, and photocatalyst mass were optimized. Considering the results provided by UV-Vis spectrophotometry and Total Organic Carbon, it was found that the prepared samples are extraordinarily efficient to degrade Congo red under visible light.