title: Titania-supported silver-based bimetallic nanoparticles as photocatalysts.
abstract: Photocatalytic process has shown recently a great potential as an environmental friendly and clean remediation technology for organic pollutants in wastewater. This work described the synthesis of silver-based bimetallic nanoparticles using colloid chemistry and the subsequent immobilization onto titania to form composite photocatalytic materials (titania-supported Ag-Pt nanoparticles). The photocatalysts were characterized by X-ray diffraction, electron microscopy, and nitrogen physisorption. The catalytic activity of the photocatalysts was evaluated by photocatalytic degradation of phenol and 2-chlorophenol (2-CP) in synthetic wastewater solutions. The photocatalytic processes were conducted in a batch photoreactor containing appropriate solutions of phenol and 2-CP with UV irradiation of 450 W. UV-visible spectrophotometer was used for analyzing the concentration of phenol and 2-CP in solutions. Parameters affecting the photocatalytic process such as the solution pH, phenol and 2-CP concentrations, and catalyst concentration were investigated. The results obtained revealed that TiO(2)-supported Ag/Pt nanoparticles showed a higher activity for UV-photocatalytic degradation of both phenol and 2-CP pollutants in the solution (as compared to the plain rutile TiO(2)). The photodegradation processes were optimized by the 0.5-g/L catalyst with a pollutant concentration of 50 mg/L for all the samples. Complete degradation for both phenol and 2-CP was achieved after 120 min.
authors.affiliation: Department of Environmental Sciences, King Abdulaziz University, Jeddah, Saudi Arabia. mabarakat@gmail.com
authors.forename: M A
authors.initials: MA
authors.lastname: Barakat
authors.forename: R I
authors.initials: RI
authors.lastname: Al-Hutailah
authors.forename: M H
authors.initials: MH
authors.lastname: Hashim
authors.forename: E
authors.initials: E
authors.lastname: Qayyum
authors.forename: J N
authors.initials: JN
authors.lastname: Kuhn
mesh_terms: D001673:Biodegradation, Environmental; D002384:Catalysis; D002733:Chlorophenols / Q000378:metabolism; D053768:Metal Nanoparticles / Q000737:chemistry*; D008854:Microscopy, Electron; D019800:Phenol / Q000378:metabolism; D010782:Photolysis; D010984:Platinum / Q000737:chemistry; D012834:Silver / Q000737:chemistry; D014025:Titanium / Q000737:chemistry*; D014466:Ultraviolet Rays; D014874:Water Pollutants, Chemical / Q000737:chemistry; D014961:X-Ray Diffraction
chemical_list: D002733:Chlorophenols; D014874:Water Pollutants, Chemical; C009495:titanium dioxide; D019800:Phenol; D012834:Silver; D010984:Platinum; D014025:Titanium; C030683:2-chlorophenol