title: Photoelectrocatalytic properties of a vertically aligned Ti-W alloy oxide nanotubes array and its applications in dye wastewater degradation.
abstract: A highly ordered and vertically oriented array of nanotubes (NTs) of mixed oxide was prepared in situ by Ti-W alloy anodization. Compared with the traditional TiO2 NTs, the photoelectrocatalytic activity of the resulting Ti-W-O NTs was greatly enhanced. Results indicated a narrowing of the band gap from 3.2 eV for pristine TiO2 to 2.7 eV for Ti-W-O NTs. Under irradiation with 254 and 365 nm UV lights, Ti-W-O NTs showed much higher photoelectroconversion efficiency (eta) than TiO2 NTs and TiO2-WO3 coating. The eta254 and eta365 on Ti-W-O NTs reached as high as 51.8% and 57.0% respectively, four to five times those on TiO2 NTs and TiO2-WO3 coating. As a result of its narrow band gap energy and fast electron-hole separation, Ti-W-O NTs presented outstanding photoelectrocatalytic features. The electrochemically assisted photocatalytic degradation of highly concentrated Rhodamine 6G wastewaters was studied. The results showed that the rates of colour and TOC removal were much higher on Ti-W-O NTs than on TiO2 NTs and TiO2-WO3 coating. The photocatalytic material obtained by alloy anodization is of significance in the advanced oxidation of environmental pollutants.
authors.affiliation: Department of Chemistry, Tongji University, 1239 Siping Road, 200092 Shanghai, China.
authors.forename: Mingfang
authors.initials: M
authors.lastname: Li
authors.forename: Guohua
authors.initials: G
authors.lastname: Zhao
authors.forename: Peiqiang
authors.initials: P
authors.lastname: Li
authors.forename: Yanan
authors.initials: Y
authors.lastname: Zhang
authors.forename: Meifen
authors.initials: M
authors.lastname: Wu
mesh_terms: D000497:Alloys / Q000737:chemistry*; D004563:Electrochemistry; D005456:Fluorescent Dyes / Q000737:chemistry*; D043942:Nanotubes / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry*; D010782:Photolysis; D012235:Rhodamines / Q000737:chemistry*; D018508:Water Purification / Q000379:methods*
chemical_list: D000497:Alloys; D005456:Fluorescent Dyes; D010087:Oxides; D012235:Rhodamines; C571978:Ti-W alloy oxide; C026188:rhodamine 6G