Summary: | 碩士 === 國立臺北科技大學 === 製造科技研究所 === 96 === The study is based on experiment design to treat the relationship between process parameters of cathode catalyst and performance of direct methanol fuel cell. The experiments are divided into three parts. First, oxidants are used to oxidize carbon nanotubes to increase the surface functional groups. Second, impregnation method is used to process the cathode catalyst and then the material characters of the cathode catalyst are analyzed. Finally, by using the so-fabricated MEA to form a direct methanol fuel cell and then to analyze the performance for discussing the relation between the process parameters of cathode catalyst and performance of direct methanol fuel cell. In the study, Raman spectrum is used to analyze the ID/IG ratio of carbon nanotubes to calculate the charge of surface functional groups; EDS is used to analyze the kind and quantity of metal on the carbon nanotubes surface; TEM is used to analyze particle size and the disparity of Pt on the carbon nanotubes surface; XRD is used to analyze crystalline and particle size of Pt to compare with TEM analysis; A fuel cell test system is used to analyze the Polarization curve of the DMFC.
In the carbon nanotubes oxidization experiment, the result reveals that the surface functional groups increase with the ID/IG ratio of carbon tubes. In the oxidative carbon nanotubes reduction Pt/CNTs catalyst experiment, H2SO4 is applied to the oxidized carbon nanotubes for the Pt/CNTs catalyst reduction and the highest peak power density is readied, which is about 3.48 mW/cm2 and the particle size is 7.24 nm. From the result which is able to show that though using HNO3 oxidization carbon nanotubes can increase the power of DMFC, but the effect is limited. From the optimization experiment results, the peak power density of Pt/CNTs catalyst with parameter optimization is 3.72 mW, which increases about 7 % compared with Pt/CNTs catalyst that only optimized with oxidize carbon nanotubes. Also, the peak power increase 7 % in comparison with Pt/CNTs catalyst that is only optimized the reduction parameters increase 102 %.
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