Photoelectrocatalytic degradation of atrazine by boron-fluorine co-doped TiO2 nanotube arrays.

Atrazine, one of the most widespread herbicides in the world, is considered as an environmental estrogen and has potential carcinogenicity. In this study, atrazine was degraded on boron-fluorine co-doped TiO2 nanotube arrays (B, F-TiO2 NTAs), which had similar morphology with the pristine TiO2 NTAs. The structure and morphology of TiO2 nanotube samples were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and UV-visible diffuse reflectance spectroscopy (DRS). It showed that the decoration of fluorine and boron made both the absorption in the visible region enhanced and the band edge absorption shifted. The efficiency of atrazine degradation by B, F-TiO2 NTAs through photoelectrocatalysis was investigated by current, solution pH, and electrolyte concentration, respectively. The atrazine removal rate reached 76% through photoelectrocatalytic reaction by B, F-TiO2 NTAs, which was 46% higher than that under the photocatalysis process. Moreover, the maximum degradation rate was achieved at pH of 6 in 0.01 M of Na2SO4 electrolyte solution under a current of 0.02 A and visible light for 2 h in the presence of B, F-TiO2 NTAs. These results showed that B, F-TiO2 NTAs exhibit remarkable photoelectrocatalytic activity in degradation of atrazine.