title: Photocatalytic activity of V doped ZnO nanoparticles thin films for the removal of 2- chlorophenol from the aquatic environment under natural sunlight exposure.
abstract: Vanadium doped ZnO powders were used as precursors to deposit thin films of V(5+) incorporated ZnO nanoparticles on glass substrates by the pulsed laser deposition technique. The observed variations in Raman signals, visible region shift in the diffuse reflectance spectra along with a small shift in the (101) reflections of the X-ray diffraction (XRD) confirmed the insertion of V(5+) ions in ZnO lattice. No other additional reflection in the XRD results other than ZnO further endorsed the occupation of lattice positions by V entities rather than independent oxide formation. The asymmetric XPS peaks of Zn2p and V2p core levels confirmed the existence of both in the vicinity. The existence of minimal proportion of V(3+) along with V(5+) states varied the alteration of the oxidation states V in the synthetic route. The SEM images at various resolutions displayed the uniform distribution identical nanoparticles without the presence of additional phases in the deposited films. The SEM cross-section measurements revealed the uniform thickness of ∼90 nm of each film, whereas the surface studies of the films were performed by AFM. The as-synthesized films were tested for photocatalytic activity in sunlight illumination for the removal of 2-chlorophenol. The unique feature of the study was the estimation of the photocatalytic activity 20 ppm of 2-chlorophenol by exposing the low exposed area. The degradation of the substrate was measured by liquid phase UV-vis spectroscopy, whereas total organic carbon measurement revealed the mineralization of the substrate. The released Cl(-) ions were also measured by ion chromatography. The estimated flatband potentials and pHzpc values of the V doped materials, by Mott-Schottky analysis and zeta potential measurements respectively, were correlated with the photocatalytic activity. The kinetics of the photocatalytic degradation/mineralization process was estimated and results were correlated with the plausible mechanism.
authors.affiliation: Center of Nanotechnology, King Abdulaziz University, Jeddah, 21589, Saudi Arabia. Electronic address: nsalah@kau.edu.sa.
authors.forename: Numan
authors.initials: N
authors.lastname: Salah
authors.affiliation: Center of Excellence in Environmental Studies (CEES), King Abdulaziz University, Jeddah, 21589, Saudi Arabia; National Centre for Physics, Quaid-e-Azam University, Islamabad 44000, Pakistan.
authors.forename: A
authors.initials: A
authors.lastname: Hameed
authors.affiliation: Center of Excellence in Environmental Studies (CEES), King Abdulaziz University, Jeddah, 21589, Saudi Arabia.
authors.forename: M
authors.initials: M
authors.lastname: Aslam
authors.affiliation: Department of Physics, King Abdulaziz University, Jeddah, 21589, Saudi Arabia.
authors.forename: Saeed S
authors.initials: SS
authors.lastname: Babkair
authors.affiliation: Sciences Faculty for Girls, King Abdulaziz University, Jeddah, 21589, Saudi Arabia.
authors.forename: F S
authors.initials: FS
authors.lastname: Bahabri
mesh_terms: D002384:Catalysis; D002733:Chlorophenols / Q000032:analysis / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry*; D010084:Oxidation-Reduction; D010782:Photolysis; D013472:Sunlight; D014639:Vanadium / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000737:chemistry*; D014961:X-Ray Diffraction; D015034:Zinc Oxide / Q000737:chemistry*
chemical_list: D002733:Chlorophenols; D014874:Water Pollutants, Chemical; D014639:Vanadium; C030683:2-chlorophenol; D015034:Zinc Oxide
keywords: 2-chlorophenol; Sunlight photocatalysis; V(5+) doped ZnO; ZnO nanoparticles film