In this study, performance of membrane electrode assembly (MEA) was studied with hydrogen and methanol/water vapor fed directly to the anode. MEA was prepared by using scandiastablized zirconia (SSZ) electrolyte and NiO-SSZ and Sr-doped lanthanum ferrite (LSF) as anode and cathode materials. A three dimensional model of solid oxide fuel cell (SOFC) has been developed and is used to predict the temperature and fuel concentration distribution across the cell. On the other hand, we designed special experimental set up for testing MEA performance. The influence of different operation parameters (temperature, fuel concentration, fuel-air flow rate...) to the MEA performance was examined. The results show the maximum power generation from MEA when fed with methanol and hydrogen. The maximum power output of 1.6 W/cm² was obtained at 750 o C with pure hydrogen. When methanol was directly used as fuel, the maximum power output was 1.2 W/cm² at same temperature.

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In the present study, the effect of support for ethanol electro-oxidation reaction was investigated on 20 percent Pt/C (E-Tek), 20 percent Pt/commercial CNT, and 20 percent Pt/home-made CNTs. Homemade CNTs were prepared by template synthesis method via chemical vapor deposition (CVD) method. Twenty percent Pt/commercial CNTs and 20 percent Pt/home-made CNTs were prepared by polyol method. The metal dispersions were determined from volumetric chemisorption measurements. These catalysts were tested as anode catalysts for the ethanol electro-oxidation reaction at room temperature by cyclic voltammetry. An optimization study was conducted to find out the optimum scan rate and optimum potential change for ethanol electro-oxidation reaction on 20 percent Pt/C (E-Tek) catalyst. Then, ethanol electro-oxidation measurements were performed on 20 percent Pt/C (E-Tek), 20 percent Pt/commercial CNTs, and 20 percent Pt/home-made CNTs catalysts in 0.5 M H2SO4 +0.5 M ethanol solution at 0.05 V/s scan rate and 1.2 V vs. NHE. Although the raw data indicated that the 20 percent Pt/commercial CNTs exhibited the worst performance, the performances of all of the catalysts were identical after normalizing the current values with respect to the exposed Pt site obtained from the volumetric hydrogen chemisorption measurements. These results indicate that only the metal dispersions improved ethanol electro-oxidation reaction and support did not have any effect on ethanol electro-oxidation reaction under the conditions used in this study.

In this study, H 2 gas produced by the hydrolysis of sodium borohydride (SBH) in an alkaline medium via phosphoric acid catalyst for PEM fuel cell applications was analyzed. The purity of H 2 gas investigated by electrocatalytic method. High purity 0.5M H 2 SO 4 solution with immersed smooth surface Pt electrodesaturated with H 2 gas produced by hydrolysis process. By considering the results of electrochemical pulse techniques and CV (cyclic voltammetry) methods on the smooth surface of Pt electrode, the purity degree of gaseous H 2 determined.

In this short review article summarizes the results of studies of catalytic and photocatalytic systems for the production of hydrogen from metal borohydride and ammonium boranes. Their performance and the main problems for the usage in portable power sources such as polyelectrolyte membrane fuel cells (PEMFC) are discussed.