Catalysis of Multi-walled Carbon Nanotubes Supported Pd_xCO_y Nanoparticles Prepared by a Pyrolysis Method Using Ionic Liquids as the Solvent toward Ethanol Oxidation Reaction

摘要

Multi-walled carbon nanotubes (MWCNTs) decorated with Pd_xCo_y (the nominal atomic ratios of Pd to Co were 3:1, 3:1.5, 3:2, 3:3, respectively) nanoparticles (denoted as Pd_xCo_y/MWCNTs) were fabricated by a simple pyrolysis process, in which room temperature ionic liquids (RTILs) of butyl-3-methylimidazolium hexafluorophosphate (denoted as [BMIM]PF_6) was used as the solvent. X-ray diffraction (XRD) and transmission electron microscopy (TEM) were all used to characterize the Pd_xCo_y/MWCNTs catalysts, showing that the Pd_xCo_y particles were dispersed on the surface of the MWCNTs with an average particle size of～25.0 nm. The electro-catalytic activity of the Pd_xCo_y/MWCNTs catalysts toward ethanol oxidation reaction (EOR) was examined by cyclic voltammetry (CV). It was revealed that the onset potential was ～90 mV lower and the peak current was about four times higher for ethanol oxidation for Pd_3Co_(1.5)/MWCNTs compared to those of Pd_3Co_1/MWCNTs. The possible catalysis mechanisms of the Pd_3Co_(1.5)/MWCNTs toward EOR were also discussed.