Electrocatalyst supports nanofiber

Pt (5 wt%) supported on platelet and ribbon graphite nanofibers exhibited similar activities to those observed by Pt (25 wt°/o) on carbon black [138], This phenomenon was attributed to the crystallographic orientations adopted by the catalyst particles dispersed on graphitic nanofiber structures [139]. Also, the electrocatalysts supported on CNFs were less susceptible to CO poisoning than Pt supported on carbon black. 

Lee, K., Zhang, J., Wang, H., and Wilkinson, D. P. Progress in the synthesis of carbon nanotube- and nanofiber-supported Pt electrocatalysts for PEM fuel cell catalysis. Journal of Applied Electrochemistry 2006 36 507-522. 

The right choice of a carbon support greatly affects cell performance and durability. The purpose of this chapter is to analyze how structure and properties of carbon materials influence the performance of supported noble metal catalysts in the CLs of the PEMFCs. The review chapter is organized as follows. In Section 12.2 we give an overview of carbon materials utilized for the preparation of the catalytic layers of PEMFC. We describe traditional as well as novel carbon materials, in particular carbon nanotubes and nanofibers and mesoporous carbons. In Section 12.3 we analyze properties of carbon materials essential for fuel cell performance and how these are related to the structural and substructural characteristics of carbon materials. Sections 12.4 and 12.5 are devoted to the preparation and characterization of carbon-supported electrocatalysts and CLs. In Section 12.6 we analyze how carbon supports may influence fuel cell performance. Section 12.7 is devoted to the corrosion and stability of carbon materials and carbon-supported catalysts. In Section 12.8 we provide conclusions and an outlook. Due to obvious space constraints, it was not possible to give a comprehensive treatment of all published data, so rather, we present a selective review and provide references as to where an interested reader may find more detailed information. 

Figure 3.5 TEM imagines for several typical electrocatalysts. (A) PtRu alloy supported on carbon particles (PtRu/C) (B) Pt supported on TiOa nanofibers (Pt/TiOa) ("Ti02-supported Pt electrocatalysts for oxygen reduction reaction", Robert Hui, and Jiujun Zbang, unpublished work) and (C) Tl407-supported Ru Pt core-shell catalyst. (For color version of this figure, the reader is referred to the online version of this book.)...

Since the discovery of carbon nanotubes in the early 1990s [273] there has been emerging interest in their applicability as catalyst supports for low-temperature PEMFCs. Recently, Lee et al. reviewed the area of Pt electrocatalyst preparation techniques using carbon nanotubes and nanofibers as supports [274]. Here, the emphasis will be on the impact of novel nanostructured carbon supports (ordered mesoporous materials, nanotubes, and nanofibers) on the electrocatalytic activity with respect to direct fuel cell anodes. 

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. 

Zaragoza-Martin F, Sopena-Escario D, MoraUon EC, Sahnas-Martinez de Lecea C. Pt/carbon nanofibers electrocatalysts for fuel cells Effect of the support oxidizing treatment. J Power Sources 2007 171 302-9. 

In this connection it can be noted that Guha et al. (2010) investigated the influence of carbon support morphology on the behavior of a PEMFC membrane electrolyte assembly. Platinum electrocatalyst particles were deposited on lower-surface-area fibrous (carbon nanofibers) and particulate (carbon blacks) supports. The performance was shown to be independent of the carbon support morphology. 

Huang JS, Hou HQ, You TY (2009) Highly efficient electrocatalytic oxidation of formic acid by electrospun carbon nanofiber-supported PtxAulOO-x bimetallic electrocatalyst. Electrochem Commun 11(6) 1281-1284... 

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