The effect of highly ordered titania nanotube structures on hydrogen gas detection

Abstract

Different titanium oxide nanotubes were synthesized by anodizing the surface of titanium foil in two electrolyte solutions containing hydrofluoric acid and ethylene glycol. The samples were heat‐treated in a furnace. The microstructure and phase transformations of the nanotubes were investigated by X‐ray diffraction and field emission–scanning electron microscope. The nanoscale geometry of the nanotubes is responsible for the outstanding hydrogen gas sensitivities. A remarkable variation in electrical conductance has been observed in titanium oxide nanotube arrays that were prepared in hydrofluoric acid. This sensor exhibits a large resistance variation in the presence of very small quantities of hydrogen gas at 25 °C. The sensors show reversibility, repeatability, negligible drift, and wide dynamic range. Copyright © 2012 John Wiley & Sons, Ltd.