One-Step Formation of WO3-Loaded TiO2 Nanotubes Composite Film for High Photocatalytic PerformanceReport as inadecuate




One-Step Formation of WO3-Loaded TiO2 Nanotubes Composite Film for High Photocatalytic Performance - Download this document for free, or read online. Document in PDF available to download.

Nanotechnology & Catalysis Research Centre NANOCAT, Institute of Postgraduate Studies IPS, University of Malaya, Kuala Lumpur 50603, Malaysia



These authors contributed equally to this work.





*

Author to whom correspondence should be addressed.



Academic Editor: Klara Hernadi

Abstract High aspect ratio of WO3-loaded TiO2 nanotube arrays have been successfully synthesized using the electrochemical anodization method in an ethylene glycol electrolyte containing 0.5 wt% ammonium fluoride in a range of applied voltage of 10–40 V for 30 min. The novelty of this research works in the one-step formation of WO3-loaded TiO2 nanotube arrays composite film by using tungsten as the cathode material instead of the conventionally used platinum electrode. As compared with platinum, tungsten metal has lower stability, forming dissolved ions W6+ in the electrolyte. The W6+ ions then move towards the titanium foil and form a coherent deposit on titanium foil. By controlling the oxidation rate and chemical dissolution rate of TiO2 during the electrochemical anodization, the nanotubular structure of TiO2 film could be achieved. In the present study, nanotube arrays were characterized using FESEM, EDAX, XRD, as well as Raman spectroscopy. Based on the results obtained, nanotube arrays with average pore diameter of up to 74 nm and length of 1.6 µm were produced. EDAX confirmed the presence of tungsten element within the nanotube arrays which varied in content from 1.06 at% to 3.29 at%. The photocatalytic activity of the nanotube arrays was then investigated using methyl orange degradation under TUV 96W UV-B Germicidal light irradiation. The nanotube with the highest aspect ratio, geometric surface area factor and at% of tungsten exhibited the highest photocatalytic activity due to more photo-induced electron-hole pairs generated by the larger surface area and because WO3 improves charge separation, reduces charge carrier recombination and increases charge carrier lifetime via accumulation of electrons and holes in the two different metal oxide semiconductor components. View Full-Text

Keywords: WO3-loaded TiO2 nanotubes; electrochemical anodization; anodization voltage; photocatalytic degradation; active surface area WO3-loaded TiO2 nanotubes; electrochemical anodization; anodization voltage; photocatalytic degradation; active surface area





Author: Wai Hong Lee †, Chin Wei Lai * and Sharifah Bee Abd Hamid †

Source: http://mdpi.com/



DOWNLOAD PDF




Related documents