An effort to develop an electrochemically smaller and well-dispersed catalytic material on a high surface area carbon material is required for fuel cell applications. In terms of pure metal catalysts, platinum has been the most common catalyst used in fuel cells. Here, a rotating disk-slurry electrode (RoDSE) technique is presented as a unique method to electrochemically prepare bulk Pt/carbon nanocatalysts material avoiding a constant contact of the carbon support to an electrode surface during the electrodeposition process. The Pt/carbon nanocatalyst was prepared by using a slurry solution that was saturated with functionalized Vulcan-XC-72R in 0.10 M normalH2SO4 . The platinum precursor added to the slurry solution was normalK2PtCl6 . The electrochemically prepared Pt/C catalyst was characterized by using transmission electron micrographs, X-ray diffraction, X-ray fluorescence, thermogravimetric analysis, and X-ray photoelectron spectroscopy techniques. Electrochemical experiments were carried out to examine their activity and stability compared to a commercial ETEK Pt/C catalyst. The RoDSE nanocatalyst that contained half of the weight percent of platinum (11%) compared to the commercial 22% Pt/Vulcan XC-72R catalyst showed similar electrochemical responses to the commercial catalyst. These results demonstrate that the use of the RoDSE technique is an effective method to prepare bulk quantities of carbon-supported platinum nanocatalysts for fuel cell applications via an electrochemical route.

Properties of PtRu nanoparticles prepared using high-intensity sonochemistry are reported. Syntheses were carried out in tetrahydrofuran (THF) containing Ru3+ and Pt4+ in a fixed mole ratio of either 1:10 or 1:1. X-ray diffraction measurements confirmed sonocation produces an alloy phase and showed that the composition of the nanometer scale metal particles is close to the mole fraction of Ru3+ and Pt4+ in solution with deviations that tend toward Ru enrichment in the alloy phase. The materials gave responses that are similar in terms of peak potential and current density, referenced to the catalyst active surface area, to those of bulk alloys in voltammetry experiments involving CO stripping and CH3OH electrochemical oxidation in 0.1 M H2SO4. The results show that sonochemical methods have the potential to produce nanometer scale bimetallic electrocatalysts that possess alloy properties. The materials have application in mechanistic studies of fuel cell reactions and as platforms for the development of CO tolerant fuel cell catalyst.

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Pt catalyst supported on nanocapsule MWCNTs-Al(2)O(3) (multi-walled carbon nanotubes, MWCNTs) catalyst has been prepared by microwave-assisted polyol process (MAPP). The results of electrochemical measurements show that the nanocapsule Pt/MWCNTs-Al(2)O(3) catalyst has higher activity due to more uniform dispersion and smaller size of Pt nanoparticles, and higher stability ascribed to the stronger metal-support interaction (SMSI) between Pt nanoparticles and nanocapsule support than in Pt/MWCNTs. Furthermore, the carbon-riveted nanocapsule Pt/MWCNTs-Al(2)O(3) catalyst has been designed and synthesized on the basis of in situ carbonization of glucose. The physical characteristics such as X-ray diffraction (XRD), energy dispersive analysis of X-ray (EDAX), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) have indicated that α-Al(2)O(3) indeed entered into the inside of the MWCNTs and formed a nanocapsule support of MWCNTs with α-Al(2)O(3) as stuffing. The accelerated potential cycling tests (APCT) show that carbon-riveted nanocapsule Pt/MWCNTs-Al(2)O(3) possesses 10 times the stability of Pt/C and has 4.5 times the life-span of carbon-riveted Pt/TiO(2)-C reported in our previous work. The significantly enhanced stability for carbon-riveted nanocapsule Pt/MWCNTs-Al(2)O(3) catalyst is attributed to the reasons as follows: the inherently excellent mechanical resistance and stability of α-Al(2)O(3) and MWCNTs in acidic and oxidative environments; SMSI between Pt nanoparticles and the nanocapsule support; the anchoring effect of the carbon layers formed during the carbon-riveting process (CRP); the increase of Pt(0) composition during CRP.