Preparation of nanosized Pt-Au alloy catalyst and its activity in methanol oxidation.
The alloy catalyst has been widely used because it will be able to improve the activity and selectivity of the single metal catalyst in a given chemical reaction. In this study, the preparation and characteristics of nanosized Pt and Au particles on alumina and their catalytic activity were described. Nanosized Pt-Au catalysts were prepared by impregnation (IMP) method and deposition (DP) method using alumina or ZnO/Al2O3 as support. The size of Pt and Au particles were observed by transmission electron microscopy (TEM), energy dispersive spectroscope (EDS), and X-ray diffraction (XRD). Catalytic activity for oxidation of methanol was measured using a flow reactor. It could be seen that the Pt particle size and dispersion in the alloy catalysts was rarely influenced by preparation methods and Au particles coated by deposition method were well dispersed. TEM images showed that Au particles were well dispersed in the Pt/Au/ZnO/Al2O3 catalyst of which Au particles was supported by deposition method. The catalytic activity for methanol are given in the order of Pt-Au[IMP]/ZnO/Al2O3 > Pt[IMP]/Au[DP]/ZnO/Al2O3 > Au[DP]/Pt[IMP]/ZnO/Al2O3 > Pt-Au[DP]/ZnO/Al2O3. Therefore, Au particle size was doing not play an important role in increasing the oxidation activity, but the Au particles may promote the methanol oxidation.
Department of Chemical Engineering, Sunchon National University, Suncheon, Jeonnam 540-742, Korea.
Ki-Joong
KJ
Kim
Yong-Hwa
YH
Kim
Woon-Jo
WJ
Jeong
Seung-Won
SW
Jeong
Jong-Che
JC
Park
Ho-Geun
HG
Ahn
D000497:Alloys / Q000737:chemistry; D002384:Catalysis; D003460:Crystallization / Q000379:methods*; D006046:Gold / Q000737:chemistry*; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D000432:Methanol / Q000737:chemistry*; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D036103:Nanotechnology / Q000379:methods; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry*; D010316:Particle Size; D010984:Platinum / Q000737:chemistry*; D013499:Surface Properties
D000497:Alloys; D046911:Macromolecular Substances; D010984:Platinum; D006046:Gold; D010100:Oxygen; D000432:Methanol