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Pt-Ru electrocatalysts

Petrii OA (2008) Pt-Ru electrocatalysts for fuel cells a representative review. J Sohd State Electrochem 12 609-642... [Pg.344]

Radmilovic V, Gasteiger HA, Ross PN. 1995. Structure and chemical composition of a supported Pt-Ru electrocatalyst for methanol oxidation. J Catal 154 98-106. [Pg.461]

Pt/Ru electrocatalysts are currently used in DMFC stacks of a few watts to a few kilowatts. The atomic ratio between Pt and Ru, the particle si2 e and the metal loading of carbon-supported anodes play a key role in their electrocatalytic behavior. Commercial electrocatalysts (e.g. from E-Tek) consist of 1 1 Pt/Ru catalysts dispersed on an electron-conducting substrate, for example carbon powder such as Vulcan XC72 (specific surface area of 200-250 m g ). However, fundamental studies carried out in our laboratory [13] showed that a 4 1 Pt/Ru ratio gives higher current and power densities (Figure 1.6). [Pg.13]

Young HC, Yong GS, Won CC, Seong IW, Hak SH (2003) Evaluation of the Nafion effect on the activity of Pt-Ru electrocatalysts for the electro-oxidation of methanol. J Power Sources 118 334 11... [Pg.261]

Reviewing the work on tire Pt-Ru electrocatalysts is beyond the scope of this article. We will briefly comment on some key advances in this area. Although early discovery by Petrii, and Bockris and Wrob Io wa established the catalytic activity of Pt-Ru alloys for methanol oxidation, despite of active investigation that followed, even the optimum composition of Pt-Ru is yet to be firmly settled. An early explanation for the mechanism by which bimetallic catalysts improve upon the performance of pure Pt, that is, the bifunctional mechanism proposed by Watanabe and Motoo, was recently challenged. [Pg.32]

IR spectroscopy was used to obtain insights on the carbon monoxide absorption and oxidation mechanism on Pt-Ru electrocatalysts. Figure 17 shows the SNIFTIR spectra of CO on submonolayer Pt deposits on Ru(OOOl). Two bipolar bands are clearly visible at potentials from 0.1 to 0.8 V. Analyses of IR spectra (vide supra) attributed the bipolar band at lower frequencies to bhie-sliifted CO (i.e., moved to higher frequency) on polycrystalline Ru, whereas the higher-frequency bipolar band represents red-sliifted CO onPt(lll). ... [Pg.35]

In addition to having a good CO tolerance, Pt-Ru electrocatalysts must also have a high activity for H2 oxidation. Comparison of the mass-specific activity of a PtRu2o electrocatalyst with a commercial Pt-Ru 1 1 alloy electrocatalyst for the oxidation of pure H2 showed that its activity is tluee times that of the commercial alloy. This indicates that even for a low Pt coverage on Ru, its activity for H2 oxidation is preserved, a prerequisite for an active CO tolerant catalyst. Comparing the CO tolerance of the PtRu2o electrocatalyst with that of two commercial Pt-Ru alloy electrocatalysts for the oxidation of 1095 ppm CO in H2 confirmed the exceptional stability of the former (Fig. 20) the measurements... [Pg.40]

XANES data show that Pt in the PtRu2o has 0.345 5d vacancy/atom. The back-bonding from the Pt to CO may decrease in this case, the likely reason for this catalyst s good CO tolerance. The weaker CO bonding on PtRu2o than on Pt or the Pt-Ru alloy was confinned by CO striping voltammetry. These data show that the electronic effect in Pt-Ru electrocatalysts may be more important than previously assumed. [Pg.44]

Characterize Pt/Ru electrocatalysts prepared by a new method involving a spontaneous deposition of Pt on Ru nanoparticles. [Pg.418]

Salgado IRC, Paganin VA, Gonzalez ER et al (2013) Characterization and performance evaluation of Pt-Ru electrocatalysts supported on different carbon materials for direct methanol fuel cells, hit J Hydrogen Energy 38 910-920... [Pg.57]

Pt-Ru electrocatalysts are generally considered to be the most active binary catalysts for the MOR. Several commercial Pt-Ru alloy nanoparticles supported on carbon black have been available for applications in DAFCs. The catalytic effect has been observed using different kinds of Pt-Ru materials, such as adsorbed Ru on bulk Pt [46, 47], UHV-evaporated Ru on bulk Pt [46, 47], Pt-Ru electrodeposits [48, 49], Pt-Ru alloys [50-60], and Pt-RuOj [63-66]. [Pg.7]

PtRu catalysts with MCMB as support [35] showed lower polarization characteristics than that with CB as support. Pt-Ru nanoparticles (1.6 nm) were supported on carbon nanotubes (200nm diameter, 8-10 um length) obtained by carbonization of PPy on an alumina membrane [36]. The amount and morphology of Pt nanoparticles depend on the types of carbon nanomaterlals, Including GNFs or CNTs [37]. Surfactant-stabilized Pt and Pt/Ru electrocatalysts for PEMFC had been prepared and investigated by X. Wang [38]. [Pg.415]

Chien CC, Jeng KT. Effective preparation of carbon nanotube-supported Pt-Ru electrocatalysts. Mater Chem Phys 2006 99 80-7. [Pg.538]

Guo J, Sun G, Wang Q, Wang G, Zhou Z, Tang S, et al. Carbon nanofibers supported Pt-Ru electrocatalysts for direct methanol fuel cells. Carbon 2006 152-7. [Pg.709]

McBreen J, Mukeijee S. In-situ X-ray-absorption studies of a Pt-Ru electrocatalyst. J Electrochem Soc 1995 142 3399-d04. [Pg.813]

Colmati F Jr, Lizcano-Valbuena WH, Camara GA, Ticianelli EA, Gonzalez ER. Carbon monoxide oxidation on Pt-Ru electrocatalysts supported on high surface area carbon. J Braz Chem Soc 2002 13 474-82. [Pg.831]

See other pages where Pt-Ru electrocatalysts is mentioned: [Pg.90]    [Pg.575]    [Pg.933]    [Pg.965]    [Pg.965]    [Pg.33]    [Pg.44]    [Pg.146]    [Pg.40]    [Pg.187]    [Pg.267]    [Pg.435]    [Pg.283]    [Pg.495]    [Pg.1034]    [Pg.80]    [Pg.72]    [Pg.123]    [Pg.133]   
See also in sourсe #XX -- [ Pg.16 ]



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