In:
ECS Meeting Abstracts, The Electrochemical Society, Vol. MA2016-02, No. 38 ( 2016-09-01), p. 2791-2791
Abstract:
Long recognised as key to the reduction of precious metal loading in PEMFC is the use of small catalyst nanoparticles (c.a. 3nm) stabilised by supporting them on high surface area carbon. However, PEMFCs using this technology achieve only 50% of the lifetime required by the US DOE’s target [1] with the oxidation of carbon supports a major lifetime limitation [2] . We have previously reported that catalysts on composite boron carbide, graphite supports show an increased durability to potential cycling below 1V and remarkably high ORR specific activities, 85% higher than commercial Pt/C [3]. Despite their excellent performance at low potentials, the presence of carbon in these catalysts still limits their durability during cycling to high potentials. We will present our latest work on catalyst supports in the Si-B-C system with the focus on eliminating carbon. Hybrid DFT/HF calculations were used to highlight boron doped boron carbide and boron doped silicon carbide as ceramics with intrinsic conductivity [Figure 1a]. To synthesise these doped ceramics with high purity, low temperature synthetic routes based on the carbo-thermal reduction of polymers were developed. These routes gave carbides with low levels of carbon impurities and provided control over the morphology of the support. This allowed the creation of high surface area supports on which platinum nanoparticles have been deposited [Figure 1b] . Electrochemical characterisation (ORR activity, accelerated degradation, etc) of the produced catalysts will also be presented. [1] Fuel Cell Technical Team Roadmap, 2013, US DOE [2] E. Antolini, and E. R. Gonzalez. Solid State Ionics, 2009, 180.9 , 746 [3] C. Jackson et al. 18 th Topical ISE Meeting 2016. [Manuscript in preparation] Figure 1
Type of Medium:
Online Resource
ISSN:
2151-2043
DOI:
10.1149/MA2016-02/38/2791
Language:
Unknown
Publisher:
The Electrochemical Society
Publication Date:
2016
detail.hit.zdb_id:
2438749-6
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