A strategy to improve the performance of TiO2 nanotube array film photocatalysts by magnetron-sputtered amorphous BiFeO3

Amorphous BiFeO3/TiO2 nanotube array thin films were prepared on indium tin oxide glass using an anodic oxidation technique coupled with magnetron sputtering. The morphology, structure, optical properties, photoelectrochemical properties, and photocatalytic activity of heterostructured nanotube array thin films with different morphologies of BiFeO3 were studied. HRTEM observations show the interface between amorphous BiFeO3 and anatase TiO2. The amorphous BiFeO3/TiO2 nanotube array thin films show enhanced visible-light absorption and outstanding separation and transfer of photoinduced charges. The BFO3-TNA sample shows excellent photocatalytic activity. By using it, 97.6% of chromium (VI) can be removed in 60 min under visible-light illumination. This work will provide a feasible route to further enhance the photocatalytic activities of visible-light responsive TiO2 nanotube array thin films as photocatalysts for rapidly removing chromium (VI) from water.