title: Magnetic TiO2-graphene composite as a high-performance and recyclable platform for efficient photocatalytic removal of herbicides from water.
abstract: A new photocatalyst, magnetic TiO2-graphene, was designed and facilely produced by combining sol-gel and assembling processes. Taking advantages of graphene and TiO2, the catalyst exhibited strong light absorption in the visible region and high adsorption capacity to organic pollutants, resulting in almost 100% photocatalytic removal efficiency of typical herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) from water under simulated solar light irradiation, far higher than 33% on commercial P25. Toxicity assessment indicates the total decomposition of the original substrate. Furthermore, the catalyst can be rapidly recovered with highly stable photocatalytic performance. After 8 successive cycles, the removal efficiency of 2,4-D maintained 97.7%, and particularly, 99.1% 2,4-D removal efficiency came back at the ninth recycle when the catalyst was re-treated by ultrasonication. Moreover, even after being laid aside for one year the catalyst still kept the 2,4-D removal efficiency as high as 95.6%. For practical application, the photocatalytic also demonstrated high removal efficiencies of herbicide 2,4-D. The photocatalyst is a promising platform for removing herbicide pollutants from water.
authors.affiliation: College of Materials Science and Engineering, Hunan University, Changsha 410082, PR China.
authors.forename: Yanhong
authors.initials: Y
authors.lastname: Tang
authors.forename: Gan
authors.initials: G
authors.lastname: Zhang
authors.forename: Chengbin
authors.initials: C
authors.lastname: Liu
authors.forename: Shenglian
authors.initials: S
authors.lastname: Luo
authors.forename: Xiangli
authors.initials: X
authors.lastname: Xu
authors.forename: Liang
authors.initials: L
authors.lastname: Chen
authors.forename: Bogu
authors.initials: B
authors.lastname: Wang
mesh_terms: D015084:2,4-Dichlorophenoxyacetic Acid / Q000737:chemistry*; D002384:Catalysis; D004926:Escherichia coli / Q000187:drug effects / Q000254:growth & development; D006108:Graphite / Q000737:chemistry* / Q000528:radiation effects; D006540:Herbicides / Q000737:chemistry* / Q000633:toxicity; D060328:Magnetic Phenomena; D058185:Magnetite Nanoparticles / Q000737:chemistry / Q000528:radiation effects / Q000648:ultrastructure; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D055668:Photochemical Processes; D059027:Recycling; D012822:Silicon Dioxide / Q000737:chemistry / Q000528:radiation effects; D013472:Sunlight; D014025:Titanium / Q000737:chemistry* / Q000528:radiation effects; D014874:Water Pollutants, Chemical / Q000737:chemistry* / Q000633:toxicity; D018508:Water Purification / Q000379:methods
chemical_list: D006540:Herbicides; D058185:Magnetite Nanoparticles; D014874:Water Pollutants, Chemical; C009495:titanium dioxide; D015084:2,4-Dichlorophenoxyacetic Acid; D012822:Silicon Dioxide; D006108:Graphite; D014025:Titanium