The Effect of Tween® Surfactants in Sol-Gel Processing for the Production of TiO2 Thin Films

Abstract

Titanium dioxide thin films were deposited using a Tween ® surfactant modified non-aqueous sol-gel method onto fluorine doped tin oxide glass substrates. The surfactant concentration and type in the sols was varied as well as the number of deposited layers. The as deposited thin films were annealed at 500 °C for 15 min before characterisation and photocatalytic testing with resazurin intelligent ink. The films were characterised using scanning electron microscopy, atomic force microscopy, X-ray diffraction, Raman spectroscopy and UV-Vis spectroscopy. Photocatalytic activity of the films was evaluated using a resazurin dye-ink test and the hydrophilicity of the films was analysed by water-contact angles measurements. Characterisation and photocatalytic testing has shown that the addition of surfactant in varying types and concentrations had a significant effect on the resulting thin film microstructure, such as changing the average particle size from 130 to 25 nm, and increasing the average root mean square roughness from 11 to 350 nm. Such structural changes have resulted in an enhanced photocatalytic performance for the thin films, with an observed reduction in dye half-life from 16.5 to three minutes.

VO2/TiO2bilayer films for energy efficient windows with multifunctional properties

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LiNbO3-based sol-gel composite ultrasonic transducer poled at low temperatures

“…LN powders were purchased from Mitsuwa Chemicals Co., Ltd AO and TO sol-gel precursor solutions were self-made one according to past studies. 34,35) It is noted that recipe of TO sol-gel was modified to keep amorphas by over adding strontianite. A ball mill was used to mix the powders and solutions.…”

Electrochemical Evaluation of Light‐Addressable Electrodes Based on TiO2 for the Integration in Lab‐on‐Chip Systems

“…The sol was synthesized with a modified non‐aqueous approach described by Anderson et al The synthesis was performed under ambient conditions and all chemicals were used without further purification. To control the speed of hydrolysis and condensation reactions, acetylacetone (61 µl) as a stabilizing agent was added dropwise to isopropanol (6.9 ml) under vigorous stirring.…”