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Herein, the preparation of nanotubular and porous TiO2 structures (TNS) is presented for photocatalytic applications. Different TNS were prepared in three different types of glycerol- and ethylene glycol-based electrolytes on a large area (approx. 20 cm2) via anodization using different conditions (applied potential, fluoride concentration). Morphology, structure, and optical properties of TNS were characterized by Scanning Electron Microscopy (SEM), X-ray Diffractometry (XRD), and Diffuse Reflectance Spectroscopy (DRS), respectively. All TNS possess optical band-gap energy (EBG) in the range from 3.1 eV to 3.2 eV. Photocatalytic degradation of caffeine was conducted to evaluate the efficiency of TNS. Overall, nanotubular TiO2 possessed enhanced degradation efficiencies (up to 50% degradation) compared to those of porous TiO2 (up to 30% degradation). This is due to the unique properties of nanotubular TiO2, e.g., improved incident light utilization. As the anodization of large areas is, nowadays, becoming a trend, we show that both nanotubular and porous TiO2 are promising for their use in photocatalysis and could be potentially applicable in photoreactors for wastewater treatment. We believe this present work can be the foundation for future development of efficient TiO2 nanostructures for industrial applications.

TiO2 nanotube (TNT) layers are generally prepared in fluoride-based electrolytes via electrochemical anodization that relies on the field-assisted dissolution of Ti metal forming nanoporous/nanotubular structures. However, the usage of fluoride...

In this study, we introduced the method for the growth of titanium molybdenum oxide (TMO) nanotubes directly from metallic precursor solid state solution and provided their structural and chemical characterization. Precursor films with content of molybdenum from 32 to 82 at% were prepared using co-deposition magnetron sputtering. The optimization of deposition parameters allowed for the growth of a continuous nanotube array with a length up to 700 nm ± 10% by anodic oxidation. Scanning electron microscopy (SEM) combined with energy-dispersive spectroscopy (EDS) revealed nanotube formation with Ti1−xMoxO2 composition, where x can reach the value of 0.5. Scanning transmission electron microscopy combined with EDS (STEM-EDS) confirmed the incorporation of Mo into the TiO2 lattice and uniform elemental distribution across the nanotube at the submicron level. The nanobeam electron diffraction (NBD) and X-ray diffraction analyses (XRD) did not show any notable crystal phase formation for the titanium molybdenum oxide phase.