Repozytorium publikacji - Politechnika Gdańska

The oriented TiO2 nanotube arrays (NTs) are identified as a stable, active and recyclable photocatalytic surface. However, their photoactivity is strictly depended on morphology (especially length), which could be controlled by anodic oxidation parameters, including electrolyte properties. To control the morphology, were successfully synthesized a series of NTs by a novel approach where ionic liquid (IL), ethylammonium nitrate [EAN][NO3], was used as an addition to an organic electrolyte. Using scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, diffuse reflectance UV-Vis spectroscopy and photoluminescence spectroscopy we are able to show how electrolyte composition influence nanotubes surface properties and photocatalytic activity. It was found that the change in the amount of [EAN][NO3] in electrolyte used for anodization in the range from 0.05 to 1.0 wt.% affected dynamic viscosity, conductivity and surface tension of electrolyte and finally alter morphology of formed nanotubes resulting in a proportional increase of the outer diameter and tube length from 105 to 140 nm and from 6.0 to 8.1 µm, respectively. The highest photoactivity (achieving high reaction rate constant, equal to k = 0.0941 min-1) and wettability was found for the sample prepared in the electrolyte containing 0.05 wt.% of [EAN][NO3] revealing the improved ability to light photoabsorption and suppression of recombination rate. It turned out that IL_NTs surface became more hydrophobic when stored in air ambience over 7 weeks after fabrication with approximately 20 – 52°. The increase of the contact angle from 9.3 to 13.1° with elongation of the tube diameter from 107 to 140 nm was also noted.

Autorzy

• Anna Pancielejko link otwiera się w nowej karcie ,
• mgr inż. Paweł Mazierski,
• dr hab. Wojciech Lisowski,
• Prof. dr hab. inż. Adriana Zaleska-Medynska,
• dr inż. Klaudia Kosek link otwiera się w nowej karcie ,
• dr hab. inż. Justyna Łuczak link otwiera się w nowej karcie