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Assembly of CeO 2-TiO 2 nanoparticles prepared in room temperature ionic liquid on graphene nanosheets for photocatalytic degradation of pollutants

Ghasemi, S ; Sharif University of Technology | 2012

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  1. Type of Document: Article
  2. DOI: 10.1016/j.jhazmat.2011.10.080
  3. Publisher: 2012
  4. Abstract:
  5. CeO 2-TiO 2 nanoparticles were prepared by the sol-gel process using 2-hydroxylethylammonium formate as room-temperature ionic liquid and calcined at different temperatures (500-700°C). CeO 2-TiO 2-graphene nanocomposites were prepared by hydrothermal reaction of graphene oxide with CeO 2-TiO 2 nanoparticles in aqueous solution of ethanol. The photocatalysts were characterized by X-ray diffraction, BET surface area, diffuse reflectance spectroscopy, scanning electron microscopy, and Fourier transformed infrared techniques. The results demonstrate that the room-temperature ionic liquid inhibits the anatase-rutile phase transformation. This effect was promoted by addition of CeO 2 to TiO 2. The addition of graphene to CeO 2-TiO 2 nanoparticles enhances electron transport and therefore impedes the charge recombination of excited TiO 2. The photodegradation results of the pollutants in aqueous medium under UV irradiation revealed that CeO 2-TiO 2-graphene nanocomposites exhibit much higher photocatalytic activity than CeO 2-TiO 2 and pure TiO 2. The photocatalytic activity of CeO 2-TiO 2-graphene nanocomposites decreases with additional increasing of the graphene content. Moreover, comparison of the photocatalytic activities of CeO 2-TiO 2-graphene with the other CeO 2-TiO 2-carbon demonstrates that CeO 2-TiO 2-graphene nanocomposites have the highest photocatalytic activity due to their unique structure and electronic properties. Chemical oxygen demand for solutions of the pollutants gave a good idea about mineralization of them
  6. Keywords:
  7. CeO 2-TiO 2 nanoparticles ; CeO 2-TiO 2-graphene nanocomposites ; Graphene ; Photocatalysis ; Room-temperature ionic liquid ; Aqueous medium ; BET surface area ; Charge recombinations ; Diffuse reflectance spectroscopy ; Electron transport ; Fourier ; Hydrothermal reaction ; Infrared technique ; Phase transformation ; Photo catalytic degradation ; Photocatalytic activities ; Room temperature ionic liquids ; TiO ; UV irradiation ; Calcination ; Electronic properties ; Ethanol ; Ionic liquids ; Nanocomposites ; Nanoparticles ; Oxide minerals ; Photocatalysts ; Photodegradation ; Pollution ; Scanning electron microscopy ; Sol-gel process ; Spectroscopy ; X ray diffraction ; Titanium dioxide ; Alcohol ; Carbon ; Cerium oxide ; Formic acid derivative ; Ionic liquid ; Nanocomposite ; Nanoparticle ; Oxide ; Ceric oxide ; Metal nanoparticle ; Alkene ; Biodegradation ; Electron ; FTIR spectroscopy ; Hydrothermal activity ; Particulate matter ; Recombination ; Reflectance ; Surface area ; Temperature effect ; Ultraviolet radiation ; Aqueous solution ; Chemical oxygen demand ; Infrared spectroscopy ; Mineralization ; Photocatalytic degradation ; Room temperature ; Ultraviolet irradiation ; Chemistry ; Pollutant ; Ultraviolet spectrophotometry ; Catalysis ; Cerium ; Environmental Pollutants ; Graphite ; Metal Nanoparticles ; Microscopy, Electron, Scanning ; Photochemistry ; Spectrophotometry, Ultraviolet ; Spectroscopy, Fourier Transform Infrared ; Temperature ; Titanium
  8. Source: Journal of Hazardous Materials ; Volume 199-200 , 2012 , Pages 170-178 ; 03043894 (ISSN)
  9. URL: http://www.sciencedirect.com/science/article/pii/S0304389411013343