Synthesis of a magnetically separable composite photocatalyst with high photocatalytic activity under sunlight

A novel magnetically separable composite photocatalyst (N-doped titania-coated γ-Fe2O3 magnetic activated carbon) was prepared. It consists of N-doped titania, activated carbon and γ-Fe2O3. The whole processes were carried out under low temperature. The prepared sample was characterized by XRD, DRS, SEM, BET and vibrating sample magnetometer (VSM). The photocatalytic activity was determined by degradation of Reactive Brilliant Red X-3B in an aqueous solution under solar irradiation. Results showed that this as-prepared composite photocatalyst exhibited much higher photocatalytic activity than Degussa P25. Furthermore, the photocatalyst can be separated easily by an external magnetic field. Thus, the photocatalyst can be recycled without mass losing, and the degradation percent of X-3B decreased less than 2% after six cycles.