Visible light-driven photoelectrocatalysis for simultaneous removal of oxytetracycline and Cu (II) based on plasmonic Bi/Bi2O3/TiO2 nanotubes

A visible light-driven photoelectrocatalytic system was constructed based on Bi/Bi 2 O 3 /TiO 2 nanotubes (NTs) to treat wastewater containing oxytetracycline and Cu 2+ mixed pollutants. The surface morphology , crystal phase, elemental composition , light absorption property and photoelectrochemical activity of the synthesized Bi/Bi 2 O 3 /TiO 2 NTs were investigated. The composite film , Bi/Bi 2 O 3 /TiO 2 NTs was used for the photoelectrochemical removal of oxytetracycline, and it had excellent visible light photoelectrocatalytic performance. Under optimal conditions, the composite film was simultaneously used to remove coexisting oxytetracycline-Cu 2+ . The study results show that the reduction of Cu 2+ on cathode was promoted by oxytetracycline while the degradation of oxytetracycline on photoanode was slightly suppressed by Cu 2+ . Also, possible photoelectrocatalytic degradation pathways for oxytetracycline-Cu 2+ were analyzed by HPLC-MS.