Porous-suspended graphite carbon doped TiO2 improves the band structure of photocatalysts to enhance photocatalytic degradation of tetracycline in water

In order to improve visible light utilization efficiency and enrich low-concentration antibiotics in water systems, a new type of floating TiO2 graphite carbon (FTDGC) photocatalyst was prepared by the one-pot method. These floating materials have good adsorption properties and sufficient mechanical strength, which makes them easy to recycle and reuse in processing. Its photocatalytic performance was evaluated by photocatalytic degradation of tetracycline (TC) in water. The results showed that FTDGC had a high adsorption degradation capacity for TC and the photocatalytic degradation process was accorded with a first-order kinetic equation. The Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy indicated the generation of Ti–C–Ti valence bonds and Ti–C–O bonds on the TiO2 surface with the modification of graphite carbon materials. Optimization of preparation conditions revealed that as the amount of activator phosphoric acid increased and the porosity of the solid surface increased, the external exposure of TiO2 made the effect of the composite catalyst more pronounced. The recycling experiment showed that FTDGC still had good degradation ability for TC after five times reuse. The catalysts developed in this research can provide a new idea and reference for the pretreatment of refractory organic wastewater, as well as for the reuse of medium water.