Development of nanopillar arrays for fabricating the electrodes of a fuel cell

• Main Authors: Du-Hsiang Tang, 湯杜翔
• Other Authors: Chin-Pao Cheng
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/39992922046352888060

碩士 === 國立臺灣師範大學 === 機電科技研究所 === 94 === Abstract A direct methanol fuel cell (DMFC) is the much-anticipated science and technology in the future, the present developing direction such as application of 3C products and portable power supplying device. However, the DMFC still has the following drawbacks to overcome, for example improve the catalyst efficiency of electrodes and reduce the methanol crossover phenomenon, it makes its output power is still unable to meet practical applications. According to the past approach, in order to make the rugged electrodes, it has to use the inductively coupled plasma reactive ion etching (ICP-RIE) technique, but these equipments are expensive. The research will integrate nanosphere lithography, photo-assisted electrochemical etching (PAECE) and electroforming techniques for fabricating perfect and high regular arrangement of the nanopillars array structure. If all techniques that we adopt can be integrated successfully, low cost, fabricating perfect and high regular arrangement of the nanopillars array can be realized. In addition, we can fabricate the electrodes in the direct methanol fuel cell by means of these techniques. Experiment results show that self-assembly nanosphere lithography, it can be used to define nano-pattern array by integrating thin photoresist and vibration method. The novel coating method of nanosphere can arrange nanosphere regularly. Nanohole can be easily obtained in PAECE process, which dimensions of width and height is 90 nm and 7.4 µm (aspect ratio, 67:1). We have finished the fabrication process of nanopillar array by using PAECE technique. Nanopillar array can be regularly arranged, which dimensions of width and height is 250 nm~300 nm and 1.56 µm (aspect ratio, 6.2:1~5.2.:1). The nanopillar electrode (9.3 mA/cm2) showed 3 times larger current density than that from planar electrode (3.1 mA/cm2) at electrode potential of 1V. We found the nanopillar electrode DMFC (58.4 µW/cm2) showed maximum 6.3 times higher power density than the planar electrode DMFC (9.3 µW/cm2) in fuel cell test. Keywords: nanopillar, photo-assisted electrochemical etching, electroforming, direct methanol fuel cell.