Preparation of Size-Controlled TiO₂ Nanoparticles and Derivation of Optically Transparent Photocatalytic Films

Abstract

TiO 2 nanoparticles were prepared by hydrothermal reaction of titanium alkoxide stabilized in acidic ethanol/water solution. The sizes of particles have been controlled to the range of 7-25 nm by adjusting the concentration of Ti precursor and the composition of the solvent system. The TiO 2 samples synthesized under this acidic ethanol/water environment were mainly primary particles in anatase phase without secondary structure. The suspension of as-prepared 7-nm-sized TiO 2 nanoparticles demonstrates long-term stability, and has been applied successfully for the fabrication of ultra-transparent particulate TiO 2 films. The photocatalytic efficiency of TiO 2 films prepared from the 7-nm-sized nanoparticles was 1.6 times of that of films derived from Degussa P25 in decomposing gaseous 2-propanol.

Hydrogen Production by Photoreforming of Renewable Substrates

“…Furthermore, increased available surface sites concentration usually improves catalyst activity [53][54][55]. Nevertheless, surface recombination of electron and holes may prevail, thus limiting the overall activity of the sample [56].…”

Magnetically Recoverable Core–Shell Nanocomposites with Enhanced Photocatalytic Activity

“…It has been pointed out in a number of prior works that the optimal size of an anatase particle for photocatalysis is around 10 nm. [33][34][35] Another reason is the SiO 2 /TiO 2 composite structure, which has been reported in many papers to show enhancement in the overall photocatalytic efficiency. [32,36] In addition, the Fe 3 O 4 core has essentially no contribution to the photocatalytic activity.…”

Effect of ultrasonication on anodic oxidation of titanium

“…Details on the measurement procedure are described elsewhere. 17) Although the absolute value is not very large, it is obvious that the annealed specimen shows a higher photocatalytic response than a typical and commercial titania (P-25, Degussa). The ultrasonic effects on N2 doping nor photocatalytic property were scarcely observed.…”