Novel magnetically separable γ-Fe2O3/Ag/AgCl/g-C3N4 composite for enhanced disinfection under visible light

A magnetically recoverable gamma-Fe2O3/Ag/AgCl/g-C3N4 nanocomposite was successfully synthesized by a combination of the solvothermal method and photodeposition approach. The obtained nanocomposite was characterized by HRTEM, SEM, XRD, PL, XPS, BET, VSM and DRS analyses, and the photocatalytic antibacterial performance of the sample was evaluated by the inactivation of Escherichia Coll (E. coil) beneath visible-light irradiation. The results showed that the gamma-Fe2O3/Ag/AgCl/g-C3N4 nanocomposite exhibited a potent bacteria disinfection activity and that the quantity of viable bacteria was nearly inactivate after being illuminated for 1 h. The reactive species scavenging experiments revealed that the hydroxyl radical and hydrogen peroxide played the most important roles in the photocatalytic bacterial inactivation. During the photocatalytic process, the relative differences between the conduction band and valence band potentials of four materials (gamma-Fe2O3, Ag, AgCl, and g-C3N4) promoted the continuous transfer of photogenerated electrons, which suppressed the recombination of electron-hole pairs and enhanced the photocatalytic antibacterial activity under visible-light irradiation.