title: Efficient removal of formaldehyde by nanosized gold on well-defined CeO₂ nanorods at room temperature.
abstract: Gold (Au) nanoparticles (NPs) supported on well-defined ceria (CeO2) nanorods with exposed {110} and {100} facets were prepared by a deposition-precipitation method and characterized by powder X-ray diffraction, micro-Raman spectroscopy, X-ray photoelectron spectroscopy, nitrogen adsorption-desorption, transmission electron microscopy, high-resolution transmission electron microscopy, and high-angle annular dark-field scanning transmission electron microscopy. Both nanometer and subnanometer gold particles were found to coexist on ceria supports with various Au contents (0.01-5.4 wt %). The catalytic performance of Au/CeO2 catalysts was examined for formaldehyde (HCHO) oxidation into CO2 and H2O at room temperature and shown to be Au content dependent, with 1.8 wt % Au/CeO2 displaying the best performance. On the basis of the results from hydrogen temperature-programmed reduction and in situ Fourier transform infrared spectroscopy observations, the high reactivity and stability of Au/CeO2 catalysts is mainly attributed to the well-defined ceria nanorods with {110} and {100} facets which present a relatively low energy for oxygen vacancy formation. Furthermore, gold NPs could induce the weakened Ce-O bond which in turn promotes HCHO oxidation.
authors.affiliation: State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology , Wuhan, Hubei 430070, China.
authors.forename: Quanlong
authors.initials: Q
authors.lastname: Xu
authors.forename: Wanying
authors.initials: W
authors.lastname: Lei
authors.forename: Xinyang
authors.initials: X
authors.lastname: Li
authors.forename: Xiaoying
authors.initials: X
authors.lastname: Qi
authors.forename: Jiaguo
authors.initials: J
authors.lastname: Yu
authors.forename: Gang
authors.initials: G
authors.lastname: Liu
authors.forename: Jinlong
authors.initials: J
authors.lastname: Wang
authors.forename: Pengyi
authors.initials: P
authors.lastname: Zhang
mesh_terms: D000327:Adsorption; D002384:Catalysis; D002563:Cerium / Q000737:chemistry*; D005557:Formaldehyde / Q000378:metabolism*; D006046:Gold / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles / Q000737:chemistry; D043942:Nanotubes; D010084:Oxidation-Reduction; D056951:Photoelectron Spectroscopy; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman; D013696:Temperature; D014961:X-Ray Diffraction
chemical_list: D005557:Formaldehyde; D002563:Cerium; C030583:ceric oxide; D006046:Gold