Fabrication of Titanium dioxide nanotube photo-electrodes in different electrolyte mixtures and the impacts on their characteristics and photo-catalytic abilities under visible light

TiO₂ nanotube arrays were fabricated using electrochemical anodization of titanium foils, where different types of electrolytes were tested to determine conceptual choice for nanotubes fabrication. These electrolytes are 1M (NH₄)₂SO₄ containing 0.5% wt NH₄F, 1M Na₂SO₄ containing 0.5% wt NH₄F, 1M NaF containing 0.5% wt (NH₄)₂SO₄ and a mixture of water: ethylene glycol 1:9 containing 0.5% wt NH₄F. The foils were marked as EG type (Ethylene Glycol), AS type (Ammonium sulfate), SS type (sodium sulfate) and SF type (sodium fluoride). The photocatalytic capabilities and characterization of the fabricated NTAs were analyzed using SEM, XRD, and DRS. The degradation ratio of designated organic pollutants (Rhodamine B) was analyzed. The obtained results have proven that foils fabricated using Ethylene glycol have significant photocatalytic abilities, with a degradation ratio of EG-SS-SF-AS types being 80% to 85%, 70% to 80%, 70% to 75% and 52% to 55%, respectively.