PtAu/MWCNTs纳米复合材料的制备及其对甲醇的电催化氧化性能的研究

In this paper, a series of catalysts (named PtAu/MWCNTs) with different Pt/Au molar ratio were prepared by reduction of H2PtCl6o6H2O and HAuCl4o3H2O with ethylene glycol as a reducing reagent and sodium citrate as a stabilizing reagent. By changing the deposition order of metals, Au@Pt/MWCNTs (PtAu = 20 wt%, and Pt/Au molar ratio was 4:1) nanocomposites were prepared by successive reduction of HAuCl4o3H2O and H2PtCl6o6H2O. XRD and TEM were adopted to characterize the nanocomposites. The result indicates that the PtAu nanoparticles with an average diameter of about 4.0 nm are supported on MWCNTs successfully. In addition, these nanocomposites show excellent catalytic activity for the oxidation of methanol, especially for the PtAu/MWCNTs nanocomposite with Pt/Au molar ratio of 4:1, which could be concluded that incorporation of an appropriate amount of Au with Pt nanoparticles can greatly enhance the activity of the catalyst. Meanwhile, it was also observed that the activity of the PtAu(4:1)/MWCNTs was better than that of Au@Pt(1:4)/MWCNTs, which may illustrate that the structure of the catalysts have a great influence on their catalytic activity.