Studying of Co-doped g-C₃N₄ and modified with Fe₃O₄ quantum dots on removing tetracycline

A new Co-doped and Fe₃O₄ quantum dots (QDs) decorated g-C₃N₄ (CN) photocatalyst applied in the tetracycline degradation under visible light irradiation, is designed and synthesized. The Fe₃O₄-QDs@Co–CN enhanced photocatalytic activity and cycling ability in comparison with individual CN significantly. It revealed a synergistic effect between the formation of Fe₃O₄-QDs and Co-doping. Results of characterization insight into the reason that Co-doped can regulate the band gap of CN, which has been proved by XPS and density functional theory (DFT). Moreover, the oxidation-reduction centre of Fe₃O₄-QDs with quantum effect can significantly boost the absorption of visible light and utilization electrons. Therefore, this work provides a broadening window for photo harvesting, charge using and separation during photocatalytic reactions.