Supported Pt on multiple wall Carbon Nanotube for the electrode application of Direct Methanol Fuel Cell

• Main Authors: yum-ming dai, 戴永銘
• Other Authors: Jih-Mirn Jehng
• Format: Others
• Language: zh-TW
• Published: 2004
• Online Access: http://ndltd.ncl.edu.tw/handle/40123902058981893625

碩士 === 國立中興大學 === 化學工程學系 === 92 === As for the CNT growth over nano-Mg-Ni alloys, the results of XRD, TGA,TEM that the optimum reaction condition nano-Mg-Ni alloy as the catalyst to perform pyrolysis of 100% CH4 to form CNTs with the flow rate about 100 ~ 120 sccm at 650℃. Raman results also indicate that the CNTs are formed as the multi-walled structure. After the purified procedures with both air oxidation at 550℃ and HCl treatment, the purity of CNT reaches to ~100%. Thus, the air oxidation step is crucial for the completed purification. The oxidation with flowing of air at high temperature can reorganize the graphite interlayers and makes the HCl easily to penetrate into the graphite interlayers to dissolve the residual catalyst. Good methods for increasing activity of catalyst in direct methanol fuel cells are decreasing the particle size of Pt and improving its dispersion. FE-SEM and XRD results indicate that the particle size of Pt supported on CNTs of electrode which synthesis under 120℃ is below 5nm and electrochemical analysis indicates the value of discharge is the best reveals the discharge is related to dispersion and the particle size of Pt. Compared with Pt supported on carbon black shows the value of discharge of Pt supported on CNTs is much better reveals CNTs have chance to take the place of traditional carbon material.