Urchin-like Material of Mesoporous Carbon Hollow Spheres Grown with Carbon Nanotubes as Cathode Support for Fuel cell
| Autor: | Wan-ting Li, 李宛庭 |
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| Rok vydání: | 2009 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 97 The urchin-like carbon material (UC) with high surface area (357~416 m2/g), sufficient electrical conductivity (47.3~59.6 Scm-1) and good chemical stability were successfully prepared by growing carbon nanotubes onto mesoporous carbon hollow spheres (MC). We prepared Pt catalyst by the reduction of citrate and then heat-treated to prepare Pt nanoparticles. Pt depositions on the urchin-like carbon was then conducted by benzylamine stabilize Pt onto the carbon supports. The main diameters based on the estimate of 200 particles selected randomly are 2.5 ± 1.8, 2.2 ± 0.4, 2.2 ± 0.5 nm for the Pt/MC, Pt/UC20 and Pt/UC45 respectively. XPS revealed the percentages of Pt (0) are given as 85.3 % for the Pt/C catalyst; this figure is higher than that of the E-TEK Pt/C catalyst, namely 73.5 %. Significant enhancement in the electrochemical active surface area (EAS) and durability of supported catalysts has been achieved by the urchin-like carbon supported Pt nanoparticles compared with carbon black Vulcan XC-72 supported ones. In addition, much higher power (~321 mW/cm2) was delivered by the urchin-like carbon supported Pt catalyst (i.e., corresponding to an enhancement of ca. 37 % in power density compared with that of E-TEK), suggesting that urchin-like carbon is a unique cathode catalyst support in proton exchange membrane fuel cell. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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