title: The investigation of the LED-activated FeFNS-TiO2 nanocatalyst for photocatalytic degradation and mineralization of organophosphate pesticides in water.
abstract: This study evaluated the preparation and characterization of an efficient doped TiO2 as a novel catalyst for degradation of diazinon model pesticide using LED-activated photocatalysis. TiO2 was doped using N, NS, FeNS, and FeFNS. The FeFNS-doped TiO2 showed the highest catalytic activity in LED/photocatalysis. FeFNS-doped TiO2 is a mesoporous nanocrystal powder with a mean pore diameter of 10.2 nm, a specific surface area of 104.4 m(2)/g and a crystallite size of 6.7 nm. LED/photocatalysis using FeFNS-doped TiO2 improved diazinon degradation by 52.3% over that of as-made plain TiO2 at an optimum solution pH of 7. The diazinon degradation in LED/photocatalysis using FeFNS-doped TiO2 increased from 44.8% to 96.3% when the catalyst concentration increased from 25% to 300%at a reaction time of 100 min. The degradation and mineralization of diazinon during LED/photocatalysis with FeFNS-doped TiO2 catalyst followed the pseudo-first-order reaction model with the rate constants of 0.973 h(-1) and 0.541 h(-1), respectively. The FeFNS-doped TiO2 was found to be an efficient catalyst that was photoactivated using UV-LED lamps. LED/photocatalysis with FeFNS-doped TiO2 catalyst is a promising alternative to conventional UV/TiO2photocatalysis for producing free OH radicals for use in the degradation and mineralization of water toxic contaminants.
authors.affiliation: Department of Environmental Health Engineering, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran.
authors.forename: Hiwa
authors.initials: H
authors.lastname: Hossaini
authors.affiliation: Department of Environmental Health Engineering, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran. Electronic address: moussavi@modares.ac.ir.
authors.forename: Gholamreza
authors.initials: G
authors.lastname: Moussavi
authors.affiliation: Department of Environmental Health Engineering, Faculty of Health, Alborz University of Medical Sciences, Karaj, Iran.
authors.forename: Mehrdad
authors.initials: M
authors.lastname: Farrokhi
mesh_terms: D002384:Catalysis; D004784:Environmental Monitoring; D058085:Iron Compounds / Q000737:chemistry*; D010755:Organophosphates / Q000737:chemistry*; D010575:Pesticides / Q000737:chemistry*; D055668:Photochemical Processes; D014025:Titanium / Q000737:chemistry*; D014865:Waste Disposal, Fluid; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D018508:Water Purification / Q000379:methods
chemical_list: D058085:Iron Compounds; D010755:Organophosphates; D010575:Pesticides; D014874:Water Pollutants, Chemical; C009495:titanium dioxide; D014025:Titanium
keywords: Elemental doping; LED; Pesticide oxidation; Photocatalysis; TiO(2) catalyst