ICMCTF2006 Session TP: TP Poster
Thursday, May 4, 2006 5:00 PM in Room Town & Country
Thursday Afternoon
Time Period ThP Sessions | Topic TS1 Sessions | Time Periods | Topics | ICMCTF2006 Schedule
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TP-1 Potassium Salt Based Alkaline Bath for Deposition of Zn-Fe Alloys
C.J. Lan, T.-S. Chin (National Tsing Hua University, Taiwan) A novel alkaline bath based on a potassium salt for the electrodeposition of Zn-Fe alloys is proposed. The lattice structure and surface morphology of the deposits were examined by XRD and SEM, respectively. The composition of deposits was quantitatively analyzed by a field emission electron probe microanalyzer (FEEPMA) and ICP-AES. Triethanolamine was used as the complexing agent to eliminate the formation of ferrous hydroxide in the strong alkaline media enabling the codeposition of zinc and iron. From cathodic linear sweep voltammograms the codeposition of Zn and Fe in the proposed bath was practicable. A Zn-Fe composition modulated alloy (CMA) was achieved by tuning the deposition variables such as ion ratio Zn/Fe, deposition current-density/voltage, temperature and the amount of additives. Within the study ranges the codeposition of Zn and Fe was found to be an anomalous one that the less noble Zn deposits preferentially to the nobler Fe. The corrosion property of the deposits depends on the Fe content. Comparing with the conventional bath of sodium salts the proposed bath possesses much higher conductivity thus exhibits more efficient and energy conserving during deposition. |
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TP-2 Study on Electrochemical Performance of PEM Fuel Cell with Designed Pt-Ru Electro-Catalyst Layers by Sputter Deposition
C.-L. Chang, T.-C. Chang, D.-Y. Wang (MingDao University, Taiwan) The sputter technique also has the potential for large-scale manufacture of fuel cell electrodes, with uniform layers containing low or ultra-low metal catalyst loading. In this study, it is investigated the performance of the prepared electrode with four models designed Pt-Ru electro-catalyst layers on the uncatalyzed gas diffusion electrode by sputter process. A fixed low Pt or Pt-Ru loading of 0.1 mg/cm2 was deposited on E-TEK electrodes for cathode and anode. Results shown that performance of the fuel cell are influenced with the microstructure of sputter-deposited Pt-Ru design layer electrodes, gas pressure, operate temperature, and internally humidify temperature. The best performance of designed layer electrodes is shown in model IV with Pt/Pt-Ru multilayers, when the gas pressure is 200 KPa, the fuel cell operates temperature at 70°C and the internally humidified temperature at 60°C. |
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TP-4 Performance of Direct Mehtanol Fuel Cell with Various Carbon Related Materials as Catalyst Supports
C.-C. Chen, C.-F. Chen (National Chiao Tung University, Taiwan) The electrocatalytic properties and performance of direct methanol fuel cell with various carbon related materials as catalyst supports were presented in this paper. Multiwall carbon nanotubes, graphitic nanoflakes, carbon black and graphitic nanoflakes attached carbon nanotubes which were deposited on carbon cloth were used as catalyst supports. Platinum nanoparticles were deposited on carbon related materials by polyol method with a loading of 0.5 mg. The observation of surface morphologies and structures of these carbon nanomaterials were carried by scanning electron microscopy and transmission electron microscopy. The active surface area of carbon related materials were calculated from cyclic voltammetry in 1.0 M sulfuric acid solution. Consequently, the graphitic nanoflakes attached carbon nanotubes reveal the highest active surface area and best cell performance. This could be attributed to the small particle size and well dispersion of platinum nanoparticles. The use of graphitic nanoflakes attached carbon nanotubes for catalyst supports not only can improve the catalyst utility but reduce the cost of DMFC. |
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TP-5 Preparation of Carbon Nanotubes in the Modified Porous Silicate Templates
C.-Y. Liu (National Chiao Tung University, Taiwan) The carbon nanotubes (CNTs) were synthesized with the novel silicate templates in the absence of metal loading was investigated. The silicate templates were prepared in the air-water interface by silica-surfactant self-assembly method. The CNTs was produced by Chemical Vapor Deposition (CVD) method. X-ray diffraction patterns were used to characterize the arrangement of the silicate materials. The High Resolution Transmission Electron Microscopy (HR-TEM), Field Emission Scanning Electron Microscopy (FE-SEM) ware used to observe the morphologies of CNTs and silicate templates and the characteristic of CNTs were analysis by Raman spectroscopy. The results indicate silicate templates have well-ordered three dimension channels. On the other hand, while the CNTs growth the narrow and uniform CNTs can be prepared with the lower methane flow rate and suitable temperature range were 640°C~670°C. It was consistency with the Raman analysis. |
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TP-6 Properties of CaCu3Ti4O12 (CCTO) Thin Film Fabricated by Sol-Gel Process
Y.-C. Chen (National Chiao-Tung University, Taiwan); L.-C. Chang (Huafan University, Taiwan); B.-S. Chiou (National Chiao-Tung University, Taiwan) The high dielectric constant material CaCu3Ti4O12 (CCTO) thin films have been fabricated by sol-gel process with molar concentration of 0.22 M on Pt/Ti/SiO2/Si substrates. Sol-gel process has several advantages such as low processing temperature, good stoichiometry control, easy of processing, and the ability to coat large area substrates, etc. In this paper, microstructures and surface morphologies of CCTO films with various heat treatments were analyzed by X-ray diffractometer (XRD) and scanning electron microscope (SEM). Dielectric constant, dielectric loss, and leakage current were measured at various temperatures. At room temperature, the dielectric constant of CCTO thin film exhibit about 5000 at 100 kHz. Increasing measuring temperature in the range from 25 to 250°C led to a decrease in the dielectric constant (5000 to 3800). With various annealing atmospheres, the dielectric properties of CCTO thin film will show the different characteristics and they will also be discussed in this paper. |