Optimization of TiO2 nanowires synthesis using hydrothermal method for hydrogen production
Effects of sonication and hydrothermal treatment time on TiO2 nanowires (TNWs) formation have been investigated. Sonication of TiO2 P25 sol was performed using sonicator water bath Cole for 0.5, 1 and 2 hours followed by hydrothermal treatment. The hydrothermal treatment was carried out in a teflon lined stainless steel autoclave for 12, 15 and 24 hours. The samples were characterized by means of Scanning Electron Microscope (SEM), X-ray powder diffractometer (XRD), UV-vis diffuse and reflectance spectroscopy (UV-vis DRS). The specific surface area of each sample was determined by the BET nitrogen gas adsorption/desorption method. The photocatalytic activity of TNWs was evaluated with photocatalytic H2 evolution from aqueous methanol solution. The result showed that the best TNWs was obtained at 1 hr sonication followed by hydrothermal process for 12 hours. By using this catalyst hydrogen production reached 82 μmol after 5h while using TiO2 P25 could only reach 23 μmol.