title: Titania-functionalized graphene oxide for an efficient adsorptive removal of phosphate ions.
abstract: Titania-functionalized graphene oxide (T-F GO), synthesized by a sol-gel process, was used as a highly efficient material to remove phosphate ions from the simulated wastewater. X-ray diffraction spectra, Fourier transform infrared spectra and scanning electron micrographs of T-F GO confirmed that titania particles were successfully grown on graphene oxide (GO) surface. The phosphate ion adsorption capacities of GO, titania and T-F GO as a function of the contact time and the pH were investigated by a UV-visible spectrophotometer. Results showed that T-F GO could absorb phosphate ions better than titania and GO could. This indicated the synergistic effect between titania and GO in the phosphate ion adsorption. The pH increment lowered the absorption capacities due to increasing the repulsion between phosphate anions and the charges on the T-F GO surface, whereas the addition of sodium ions increased the adsorption capacities. Also, phosphate ions were absorbed by specific sites of T-F GO and formed a monolayer on its surface. Finally, the maximum adsorption capacity of T-F GO was 33.11 mg/g at pH 6, much higher than those of GO and titania. Therefore, T-F GO could be a promising material to remove phosphate ions from wastewater in the future.
authors.affiliation: Materials Science and Engineering Program, Faculty of Science, Mahidol University, Rama VI Road, Bangkok 10400, Thailand.
authors.forename: Samita
authors.initials: S
authors.lastname: Sakulpaisan
authors.affiliation: Department of Chemistry, Faculty of Science, Mahidol University, Rama VI Road, Bangkok 10400, Thailand. Electronic address: thammasit.von@mahidol.ac.th.
authors.forename: Thammasit
authors.initials: T
authors.lastname: Vongsetskul
authors.affiliation: Department of Chemistry, Faculty of Science, Mahidol University, Rama VI Road, Bangkok 10400, Thailand.
authors.forename: Sakultip
authors.initials: S
authors.lastname: Reamouppaturm
authors.affiliation: Department of Chemistry, Faculty of Science, Mahidol University, Rama VI Road, Bangkok 10400, Thailand.
authors.forename: Jakkrawut
authors.initials: J
authors.lastname: Luangkachao
authors.affiliation: Department of Chemistry, Faculty of Science, Mahidol University, Rama VI Road, Bangkok 10400, Thailand.
authors.forename: Jonggol
authors.initials: J
authors.lastname: Tantirungrotechai
authors.affiliation: Department of Chemistry, Faculty of Science, Mahidol University, Rama VI Road, Bangkok 10400, Thailand.
authors.forename: Pramuan
authors.initials: P
authors.lastname: Tangboriboonrat
mesh_terms: D000327:Adsorption; D006108:Graphite / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008855:Microscopy, Electron, Scanning; D010710:Phosphates / Q000737:chemistry* / Q000302:isolation & purification*; D012964:Sodium / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D014025:Titanium / Q000737:chemistry*; D014865:Waste Disposal, Fluid / Q000379:methods; D062065:Wastewater / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000302:isolation & purification; D014961:X-Ray Diffraction
chemical_list: D006108:Graphite; D010710:Phosphates; D012964:Sodium; D014025:Titanium; D062065:Wastewater; D014874:Water Pollutants, Chemical; C009495:titanium dioxide
keywords: Graphene oxide; Phosphate; Titania