Surface roughening and top opening of single crystalline TiO2 nanowires for enhanced photocatalytic activity

Abstract One dimensional (1D) single crystalline nanostructures facilitate electron transport and reduce the charge recombination; whilst nanotubular structure and a roughened surface provide more active sites as well as more opportunities for target molecules to reach the photocatalyst. As a result, TiO 2 thin films with such a structural design can be anticipated to possess excellent photocatalytic activity. In this study, top opened nanowires with nanoprotrusions on the surface, which are hierarchical yet single crystalline as a whole, were synthesized by a simple acid treatment at 80 °C for 36 h of hydrothermally synthesized titanate nanowires, followed by a final calcination at 450 °C for 1 h. The hierarchical TiO 2 films exhibited significantly enhanced efficiency when utilized to assist the photodegradation of rhodamine B and phenol in water under UV light illumination.