Studying the Dependences of the Structure, Composition, and Photoelectrochemical Properties of Anodic Titanium Dioxide Nanotubes on the Synthesis Time and Post-Treatment Temperature

The development of UV sensors with a narrow and easily tunable sensitivity range is an urgent problem for detecting UV radiation and determining its spectral composition. This problem can be solved using titanium dioxide nanotubes (TiO2 NT) arrays as resistive photodetectors. In this study, the dependences of the quantum efficiency spectra of TiO2 NT nanotube arrays on the anodic oxidation time and heat treatment temperature have been described. TiO2 NT nanotube arrays have been obtained by anodic oxidation of titanium foil in a fluorine-containing ethylene glycol-based electrolyte in the potentiostatic mode. The results of a scanning electron microscopy study of the morphology of TiO2 NT nanostructures and a Raman scattering study of the phase composition of the samples and their luminescence intensity as functions of the anodic oxidation time and post-treatment temperature are reported. The data of the photocurrent spectroscopy measurements of the quantum efficiency of TiO2 NT nanotube arrays are presented. It has been found that the maximum efficiency at a wavelength of 360 nm is characteristic of the samples formed within 1 h and heat-treated at a temperature of 400°C and the maximum quantum efficiency corresponding to wavelengths less than 300 nm is characteristic of the samples subjected to anodic oxidation for 5 min and heat-treated at a temperature of 350°C.