Photocatalytic degradation of ofloxacin in water assisted by TiO nanowires on carbon cloth: contributions of HO addition and substrate absorbability.

Vertically aligned TiO nanowires demonstrate exceptional photoactivity owing to their high specific surface area and improved charge separation; however, their unsatisfactory interaction with target contaminants diminishes photocatalytic degradation efficiency in water. Here, we present a mild solution method to precipitate anatase TiO nanowire arrays, measuring 1.5 μm in thickness, over carbon cloth to ensure substantial interactions with target pollutants and, in turn, a superior photoactivity. Compared to TiO nanowire arrays grown on metallic Ti substrates, TiO nanowires supported on carbon cloth substrates demonstrate markedly superior efficiency in the photocatalytic degradation of ofloxacin (OFL) molecules in water when exposed to UV light. The TiO nanowires remove 90-97% OFL in water with a high initial concentration of 50 ppm in 6 h under UV light irradiation for up to six cycles. The contributions of the hydrogen peroxide (HO) additive were also studied. An enhanced efficiency could be achieved only when the HO in water reaches a critical amount, below which a negative effect is noted. This investigation demonstrates the potential of improving the photoactivity of one-dimensional TiO nanostructures by utilizing a highly adsorptive substrate, which can help mitigate the effects of hazardous materials in water.