title: Spectroscopic analyses of the photocatalytic behavior of nano titanium dioxide.
abstract: Nano titanium dioxide TiO2 was synthesized using hydrolysis method then subjected to several characterizations. XRD revealed that the as-prepared sample is pure anatase phase and after calcinations at 500°C 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.
authors.affiliation: Spectroscopy Department, National Research Centre, 12311 Dokki, Cairo, Egypt.
authors.forename: Aly
authors.initials: A
authors.lastname: Okasha
authors.affiliation: Chemistry Department, Faculty of Women for Arts, Science and Education, Ain Shams University, 11757 Cairo, Egypt.
authors.forename: Fathia
authors.initials: F
authors.lastname: Gomaa
authors.affiliation: Physics Department, Faculty of Women for Arts, Science and Education, Ain Shams University, 11757 Cairo, Egypt.
authors.forename: Hanan
authors.initials: H
authors.lastname: Elhaes
authors.affiliation: Building Physics and Environment Institute, Housing & Building National Research Center (HBRC), 12311 Dokki, Cairo, Egypt.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Morsy
authors.affiliation: Building Physics and Environment Institute, Housing & Building National Research Center (HBRC), 12311 Dokki, Cairo, Egypt.
authors.forename: Sherif
authors.initials: S
authors.lastname: El-Khodary
authors.affiliation: Spectroscopy Department, National Research Centre, 12311 Dokki, Cairo, Egypt.
authors.forename: Ahmed
authors.initials: A
authors.lastname: Fakhry
authors.affiliation: Spectroscopy Department, National Research Centre, 12311 Dokki, Cairo, Egypt. Electronic address: medahmed6@yahoo.com.
authors.forename: Medhat
authors.initials: M
authors.lastname: Ibrahim
mesh_terms: D002384:Catalysis; D008751:Methylene Blue / Q000737:chemistry*; D008958:Models, Molecular; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D010782:Photolysis; D014025:Titanium / Q000737:chemistry*; D014466:Ultraviolet Rays
chemical_list: C009495:titanium dioxide; D014025:Titanium; D008751:Methylene Blue
keywords: Anatase TiO(2); FTIR; HRTEM; Molecular modeling; Photo-degradation; XRD