FUEL 179 |
| Reducing platinum usage or replacing it with non-platinum catalyst attracts significant efforts in proton exchange membrane fuel cell (PEMFC) research. We report here our recent results on the synthesis and characterization of Pt-free carbon nanotubes with “built-in” catalytic active sites towards the oxygen reduction reaction (ORR). A variety of carbon nanotubes were successfully prepared through a specially designed chemical vapor deposition process, during which nitrogen-containing molecules and transition metal organometallics were introduced in order to incorporate catalytic active site into the graphitic structure of carbon nanotube. Cyclic voltammetry study demonstrated that the carbon nanotubes thus prepared had improved electrocatalytic activities toward the ORR reaction. In situ X-ray absorption spectroscopy study also indicated a change of transition metal valance state and coordination structure during the catalytic activation of oxygen. Details about the effect of the synthesis condition on nanotube structure, ORR activity, and active sites will be discussed. |
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Chemistry and Applications of Carbon Nanotubes and Nanoparticles
9:00 AM-11:50 AM, Wednesday, 13 September 2006 Palace -- Napa Room, Oral
Division of Fuel Chemistry |