title: Morphology controlled bulk synthesis of disc-shaped WO3 powder and evaluation of its photocatalytic activity for the degradation of phenols.
abstract: The surfactant assisted synthesis of disc-shaped WO3 powder and its photocatalytic performance in sunlight exposure is reported. UV-vis DRS, XRD and FESEM characterized the synthesized WO3. The synthesized powder exhibited a bandgap of ∼2.55eV with cubic lattice and high crystallinity. The photocatalytic activity of the synthesized WO3 was examined for the degradation of phenol, resorcinol, 2-chlorophenol and 2-nitrophenol in complete spectrum and visible segment of sunlight. The highly efficient degradation/mineralization of 2-chloro and 2-nitrophenol compared to that of phenol and resorcinol, under identical experimental conditions, suggested the regulatory role of substituents attached to the aromatic ring in degradation/mineralization process. The time-scale HPLC degradation profiles, identification of intermediates by GC-MS and removal of organic carbon during the course of reaction were utilized to approximate the possible route of degradation/mineralization of phenolic substrates. The measurement of the anions released during the photocatalytic process was used to identify the nature of the major oxidants (O2(•-), OH(•)) and the possible interaction sites. A significant decrease in the photocatalytic activity of synthesized WO3, ∼50%, was observed in visible portion of sunlight however, a sustained activity was observed in the repeated exposures.
authors.affiliation: Centre of Excellence in Environmental Studies (CEES), King Abdulaziz University, Jeddah 21589, Saudi Arabia.
authors.forename: M
authors.initials: M
authors.lastname: Aslam
authors.affiliation: Centre of Excellence in Environmental Studies (CEES), King Abdulaziz University, Jeddah 21589, Saudi Arabia; Chemistry Department, Faculty of Science, King Abdulaziz University, PO Box 80203, Jeddah 21589, Saudi Arabia.
authors.forename: Iqbal M I
authors.initials: IM
authors.lastname: Ismail
authors.affiliation: Centre of Excellence in Environmental Studies (CEES), King Abdulaziz University, Jeddah 21589, Saudi Arabia.
authors.forename: S
authors.initials: S
authors.lastname: Chandrasekaran
authors.affiliation: Centre of Excellence in Environmental Studies (CEES), King Abdulaziz University, Jeddah 21589, Saudi Arabia; National Centre for Physics, Quaid-e-Azam University, Islamabad 44000, Pakistan. Electronic address: afmuhammad@kau.edu.sa.
authors.forename: A
authors.initials: A
authors.lastname: Hameed
mesh_terms: D002384:Catalysis; D002851:Chromatography, High Pressure Liquid; D008401:Gas Chromatography-Mass Spectrometry; D008855:Microscopy, Electron, Scanning; D010087:Oxides / Q000138:chemical synthesis* / Q000737:chemistry; D010636:Phenols / Q000737:chemistry*; D010777:Photochemistry; D011208:Powders; D013056:Spectrophotometry, Ultraviolet; D014414:Tungsten / Q000737:chemistry; D014961:X-Ray Diffraction
chemical_list: D010087:Oxides; D010636:Phenols; D011208:Powders; C511604:tungsten oxide; D014414:Tungsten
keywords: Disc-shaped WO(3); Phenol degradation; Sunlight photocatalysis