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The defense date of the thesis is 2016-08-16
The current date is 2019-03-21
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URN etd-0815116-165243 Statistics This thesis had been viewed 470 times. Download 0 times. Author Tsung-Wei Ho Author's Email Address No Public. Department Mechanical Engineering Year 2015 Semester 2 Degree Master Type of Document Master's Thesis Language zh-TW.Big5 Chinese Page Count 45 Title Application of electro-forcespinning technique for the fabrication of PVP nanofibers Keyword Nanofibers Fuel Cell PVP Electro-forcespinning Electro-forcespinning PVP Fuel Cell Nanofibers Abstract Electrospinning technology has been used to fabricate the catalyst layer in the electrode of a fuel cell system. But one of the major disadvantages of this technique is the low production rate of nanofibers. Hence, how to increase the efficiency of production rate becomes an important issue. In this study, we use the electro-forcespinning technique to fabricate PVP nanofibers and examine the possibility to increase the production rate of nanofibers. Three major factors are considered in the experiments, including the PVP concentration, rotation speed of the spinneret, and strength of the applied electrical field. The morphology of collected nanofibers are examined and analyzed by the scanning electron microscope (SEM) to evaluate the feasibility of this technique.
The results show that a lower PVP concentration benefits the reduction of fiber diameter. It is found that the mean fiber diameter is about 300 nm when a PVP solution with concentration of 5% is used in the experiment. However, a lot of droplets and lumps appear and cause poor morphology of nanofibers. A higher rotation speed can improve the fiber morphology, but its effect on the reduction of fiber diameter is quite limited. A higher electrical field tends to decrease the fiber diameter and show better morphology of nanofibers. In summary, the case of 7% of PVP solution with rotation speed of 600 rpm and electrical field of 1.3 kV/cm is found to give the best quality of nanofibers. The results indicate that the electro-forcespinning technique, which combines both electrospinning and forcespinning technologies, has great potential to be used for the production of PVP nanofibers as the precursor for the fabrication of Pt nanofibers.
Advisor Committee Min-Hsing, Chang - advisor
An-Cheng Ruo - co-chair
Ching-Chih Tai - co-chair
Files Date of Defense 2016-07-06 Date of Submission 2016-08-16