title: Assembly of CeO2-TiO2 nanoparticles prepared in room temperature ionic liquid on graphene nanosheets for photocatalytic degradation of pollutants.
abstract: 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.
authors: Department of Chemistry, Sharif University of Technology, P.O. Box 11365-9516, Tehran, Iran.
authors: S
authors: S
authors: Ghasemi
authors: S Rahman
authors: SR
authors: Setayesh
authors: A
authors: A
authors: Habibi-Yangjeh
authors: M R
authors: MR
authors: Hormozi-Nezhad
authors: M R
authors: MR
authors: Gholami
mesh_terms: D002384:Catalysis; D002563:Cerium / Q000737:chemistry*; D004785:Environmental Pollutants / Q000737:chemistry*; D006108:Graphite; D053768:Metal Nanoparticles; D008855:Microscopy, Electron, Scanning; D010777:Photochemistry; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared; D013696:Temperature; D014025:Titanium / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D004785:Environmental Pollutants; C009495:titanium dioxide; D002563:Cerium; C030583:ceric oxide; D006108:Graphite; D014025:Titanium