Microstructure and photocatalytic activity of titanium dioxide nanoparticles (original) (raw)

Spectroscopic analyses of the photocatalytic behavior of nano titanium dioxide

Nano titanium dioxide TiO2was synthesized using hydrolysis method then subjected to several characterizations. XRD revealed that the as-prepared sample is pure anatase phase and after calcinations at 500C for 3 h the crystallinity has increased. The crystallite size calculated by Debye–Scherrer’s formula is 8 nm. The HRTEM image shows an average size of about 9 nm, which is close to the XRD calculation from Scherrer’s formula. PM3 semiempirical quantum mechanical calculations were conducted to present the electronic as well as thermal properties for TiO2. FTIR spectra between 800 and 400 cm 1 are the verification for the lattice vibrations of anatase TiO2. The photo catalytic degradation of methylene blue (MB) was tested by the prepared nano TiO2. Results indicate that, the maximum degradation efficiency reached 94.4% after 120 min of UV irradiation. This increase in the degradation efficiency of TiO2 could be attributed to the reduction in particle size that enhanced the crystallinity as a result of heat treatment

A study of the photocatalytic activity of titanium dioxide nanopowders

Russian Journal of Applied Chemistry, 2008

Photodestruction and adsorption of dyes in aqueous suspensions of nanopowders of titanium dioxide of anatase modification was studied. The photocatalytic activity of titanium dioxide nanopowders was examined in relation to the dispersity of particles and pH of the medium.

Characterization and photocatalytic activities of nanosized titanium dioxide thin films

2011

Thin films of titanium dioxide with high surface area are prepared by sol-gel dip-coating technique. In this regards, Titania nano sols with high photocatalytic activity were prepared by dissolving titanium alkoxide in alcohol and water under acidic conditions. Photocatalytic activities of titanium dioxide thin films were measured in the presence of methylene blue. Microstructure and photocatalytic activity of the films, nanopowders and titanium dioxide sols were investigated using X-ray diffraction, scanning electron microscopy, specific surface area, zeta sizer and ultraviolet-visible spectrometry techniques. Particle size analysis of sols showed that the mean particle sizes were 15 to 128 nm. X-ray diffraction analyses revealed that anatase crystal structure was produced with crystallite size below 11 nm. Increasing mass percent of anatase phase and specific surface area, enhance the photocatalytic activity. Scanning electron microscopy images showed that the addition of methylce...

Synthesis and photocatalytic activity of TiO2 Nanoparticles

Titanium dioxide (TiO2) nanoparticles have been synthesized by sol gel method. The synthesized nanoparticles followed by calcinations at different temperatures in the range 200-800°C for 2 hours. Both the evolution of the crystal size and nature of the phases were studied as a function of annealing temperatures. These materials display a good thermal stability up to 400°C, in term of crystal size، and up to 600°C, regarding the crystalline phase. The phase purity and crystallite size of as grown TiO2 particles were characterized via X-ray diffraction (XRD). The characterized results indicated that the synthesized TiO2 powders had a pure two phases anatase and rutile structures and the average particle sizes were about 5-53 nm. The synthesized TiO2 nanoparticles exhibited 1.0053% time higher photocatalytic activity for Bismarck Brown R than that of commercial Hombikate (UV100) .