title: Synthesis of TiO2 and TiO2-Pt and their application in photocatalytic degradation of humic acid.
abstract: The deposit of noble metal on titanium dioxide (TiO2) has been considered as an effective strategy to improve the activity of TiO2. In this study, TiO2 nanoparticles were prepared using a sol-gel route followed by heat treatment at elevated temperatures (573 K, 773 K, and 973 K). TiO2-Pt catalyst (1 wt%) was prepared by depositing Pt on the surface of the prepared TiO2 nanoparticles. TiO2 and TiO2-Pt were used as heterogeneous catalysts to remove humic acid with UV-light (120 W) illumination. TiO2 prepared at low temperature with smaller particle size and larger specific surface area had stronger activity on humic acid degradation. Deposit of Pt would favor separation of photogenerated charges and enhance the photocatalyst activity, but its coating of the active site also inhibited degradation of humic acid. The addition of H202 enhanced degradation of humic acid for more active oxygen produced. Low pH (pH = 4) was helpful to adsorb humic acid on the surface of TiO2 and, correspondingly, enhance degradation of humic acid (44.4%).
authors.forename: Wenzhao
authors.initials: W
authors.lastname: Chen
authors.forename: Xianqiang
authors.initials: X
authors.lastname: Ran
authors.forename: Xu
authors.initials: X
authors.lastname: Jiang
authors.forename: Hongyang
authors.initials: H
authors.lastname: Min
authors.forename: Dandan
authors.initials: D
authors.lastname: Li
authors.forename: Liyin
authors.initials: L
authors.lastname: Zou
authors.forename: Jianwei
authors.initials: J
authors.lastname: Fan
authors.forename: Guangming
authors.initials: G
authors.lastname: Li
mesh_terms: D002384:Catalysis; D006812:Humic Substances; D006861:Hydrogen Peroxide / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D053758:Nanoparticles; D010782:Photolysis; D010984:Platinum / Q000494:pharmacology*; D014025:Titanium / Q000494:pharmacology*; D018508:Water Purification / Q000379:methods*
chemical_list: D006812:Humic Substances; C009495:titanium dioxide; D010984:Platinum; D006861:Hydrogen Peroxide; D014025:Titanium