title: Photodegradation performance and mechanism of 4-nonylphenol by WO3/TiO2and TiO2nanotube array photoelectrodes.
abstract: TiO2Nanotube arrays (TNA) and WO3-coated TNA photoelectrodes were fabricated using an in situ anodization and pulse electrochemical deposition technology. The performance of the TNA photoelectrodes in the photocatalytic (PC) and photoelectrocatalytic (PEC) degradation of 4-nonylphenol (4-NP) was investigated. The effects of the initial pH and the anions on the degradation rates and reaction mechanism of 4-NP were studied by the photoluminescence (PL) spectra and electrochemical impedance spectra (EIS). The degradation of 4-NP was fitted to a first-order reaction, and the apparent kinetic constants were 1.9 × 10-2min-1for TNA photoelectrodes and 2.4 × 10-2min-1for WO3/TNA photoelectrodes. When a bias potential of 1.0 V was applied, the values for TNA and WO3/TNA photoelectrodes increased to 2.5 × 10-2and 3.0 × 10-2min-1, respectively. The degradation of 4-NP was controlled by a charge-transfer process one. WO3-decorated TNA photoelectrodes could increase the adsorption of 4-NP and promote its degradation. For the TNA and WO3/TNAs photoelectrodes, acid and alkaline solutions could facilitate the formation of hydroxyl radicals, whereas the removal of 4-NP was inhibited. The presence of [Formula: see text] , Cl-, [Formula: see text] and [Formula: see text] has a negative effect on the formation of •OH, so did the removal of 4-NP. For the TNA photoelectrodes, the inhibition effect of [Formula: see text] on the formation of hydroxyl radicals and the removal of 4-NP was the most serious compared with that of [Formula: see text], Cl-and [Formula: see text] , while for the WO3/TNA photoelectrodes the inhibition effect of [Formula: see text] on the removal of 4-NP was maximum.
authors.affiliation: a Qingdao Engineering Research Center for Rural Environment, College of Resource and Environment , Qingdao Agricultural University , Qingdao , People's Republic of China.|b The Key Laboratory of Marine Environmental Science and Ecology , Ministry of Education, Ocean University of China , Qingdao , People's Republic of China.|c College of Science and Information , Qingdao Agricultural University , Qingdao , People's Republic of China.
authors.forename: Yanjun
authors.initials: Y
authors.lastname: Xin
authors.affiliation: a Qingdao Engineering Research Center for Rural Environment, College of Resource and Environment , Qingdao Agricultural University , Qingdao , People's Republic of China.
authors.forename: Gang
authors.initials: G
authors.lastname: Wang
authors.affiliation: a Qingdao Engineering Research Center for Rural Environment, College of Resource and Environment , Qingdao Agricultural University , Qingdao , People's Republic of China.
authors.forename: Xiangwei
authors.initials: X
authors.lastname: Zhu
authors.affiliation: b The Key Laboratory of Marine Environmental Science and Ecology , Ministry of Education, Ocean University of China , Qingdao , People's Republic of China.
authors.forename: Mengchun
authors.initials: M
authors.lastname: Gao
authors.affiliation: c College of Science and Information , Qingdao Agricultural University , Qingdao , People's Republic of China.
authors.forename: Yongping
authors.initials: Y
authors.lastname: Liu
authors.affiliation: a Qingdao Engineering Research Center for Rural Environment, College of Resource and Environment , Qingdao Agricultural University , Qingdao , People's Republic of China.
authors.forename: Qinghua
authors.initials: Q
authors.lastname: Chen
mesh_terms: D004566:Electrodes; D043942:Nanotubes / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry*; D010636:Phenols / Q000737:chemistry*; D055668:Photochemical Processes; D010782:Photolysis; D014025:Titanium / Q000737:chemistry*; D014414:Tungsten / Q000737:chemistry*
chemical_list: D010087:Oxides; D010636:Phenols; C009495:titanium dioxide; C511604:tungsten oxide; D014025:Titanium; C041594:4-nonylphenol; D014414:Tungsten
keywords: 4-nonylphenol; Photoelectrocatalytic; TiO2 nanotube array; WO3; anion