Enhanced photocatalytic performance of hydrothermally synthesized TiO2 nanowires for H2 production via water splitting

The effective separation and high mobility of photogenerated charge carriers are important in order to enhance the photocatalytic activity of material. The one-dimensional nanostructures are providing the path for the photogenerated charge carriers resulting higher photocatalytic activity. Herein, highly crystalline Titanium dioxide (TiO 2 ) nanowires (TNWs) having anatase phase were synthesized using hydrothermal method by varying the reaction time and temperatures. The synthesized TNWs were characterized using various techniques. Structural study revealed the formation of anatase TiO 2 along with a minor percentage of the rutile phase. Morphological study indicates the growth of TiO 2 nanowires originated from spheres-wires-flakes as a function of reaction time and temperature. FE-TEM image of TiO 2 nanowires prepared at 150 ℃ for 72 h shows complete formation of nano-wires with 7–10 nm diameter. Photocatalytic performance of the synthesized TiO 2 nanowires was investigated by observing the hydrogen (H 2 ) generation via water splitting and degradation of aqueous methylene blue (MB) dye under a 400 W mercury vapor lamp respectively. Among the prepared samples, the TiO 2 nanowires prepared at 150 ℃ for 48 h showed the highest H 2 generation of 7464.28 μmol/0.1 gm higher than the Degussa TiO 2 . Further, the same nanostructured TiO 2 shows the 100% MB degradation within 30 min (K app = 13.54 × 10 −2 min −1 ). Synthesis of TiO2 nanowires at different temperatures and time • Uniform sized TiO 2 nanowires were successfully synthesized using hydrothermal method. • The obtained H 2 generation and MB dye degradation results compared with commercial TiO 2 powder results (Aldrich TiO 2 and Degussa P25) and reported highest photocatalytic activity. • Almost 1.8 times enhancement in the H 2 generation via photocatalytic water splitting is observed over TiO 2 nanowires than Aldrich TiO 2 and 1.34 times than Degussa P25. • The photocatalytic MB degradation rate is almost 3.9 times and 1.7 times higher than Aldrich TiO 2 and 1.7 times higher than Degussa P25.