Photocatalytic degradation of selected herbicides in aqueous suspensions of doped titania under visible light irradiation.
The aim of this work was to study the efficiency of Fe- and N-doped titania suspensions in the photocatalytic degradation of the herbicides RS-2-(4-chloro-o-tolyloxy)propionic acid (mecoprop, MCPP), (4-chloro-2-methylphenoxy)acetic acid (MCPA), and 3,6-dichloropyridine-2-carboxylic acid (clopyralid, CP) under the visible light (lambda > or = 400 nm) irradiation. The obtained results were compared with those of the corresponding undoped TiO(2) (rutile/anatase) and of the most frequently used TiO(2) Degussa P25. Computational modeling procedures were used to optimize geometry and molecular electrostatic potentials of MCPP, MCPA and CP and discuss the obtained results. The results indicate that the efficiency of photocatalytic degradation is greatly influenced by the molecular structure of the compound. Lowering of the band gap of titanium dioxide by doping is not always favorable for increasing photocatalytic efficiency of degradation.
Sojić
Daniela V
DV
Department of Chemistry, Biochemistry and Environmental Protection, Faculty of Sciences, University of Novi Sad, Trg D. Obradovića 3, 21000 Novi Sad, Serbia. daniela.sojic@dh.uns.ac.rs
Despotović
Vesna N
VN
Abazović
Nadica D
ND
Comor
Mirjana I
MI
Abramović
Biljana F
BF
D002384:Catalysis; D003198:Computer Simulation; D006540:Herbicides / Q000737:chemistry* / Q000528:radiation effects*; D007501:Iron / Q000737:chemistry; D008027:Light; D008855:Microscopy, Electron, Scanning; D015233:Models, Statistical; D009584:Nitrogen / Q000737:chemistry; D010777:Photochemistry; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared; D013535:Suspensions; D014025:Titanium / Q000737:chemistry* / Q000528:radiation effects*; D014867:Water; D014961:X-Ray Diffraction
D006540:Herbicides; D013535:Suspensions; D014867:Water; C009495:titanium dioxide; D014025:Titanium; D007501:Iron; D009584:Nitrogen