In-situ X-ray absorption near-edge structure (XANES) experiments were performed on a working reformateair fuel cell to study the structure of carbon supported Pt-Ru anode electro-catalyst. The fuel cell was operated in a normal mode without the use of supplemental electrolytes. A fresh membrane electrode assembly (MEA) and a conditioned MEA were studied at different operating conditions of the fuel cell and different feed (pure H 2 or H 2 /CO [100 ppm CO]) at the anode. The in-situ Pt L III -edge and Ru K-edge XANES of the fuel cell MEAs showed metallic characteristics under all operating conditions. These results demonstrate that, under the reducing conditions of normal fuel cell operation, the Pt-Ru catalyst exists as a metallic phase(s).

A chiral nematic liquid crystal-photopolymerizable monomer-chiral azobenzene compound composite was prepared and then polymerized under UV irradiation. The reflection wavelength of the composite can be extended to cover the 1000-2400 nm range and also be adjusted to the visible light region by controlling the concentration of chiral compounds.

The rotating disk electrode technique was employed to investigate the methanol electrooxidation reaction (MOR) on a polycrystalline Pt surface in acidic medium to elicit quantitative kinetic information and to investigate the MOR reaction mechanism. The Tafel slope was 125 mV/decade, suggesting that the first electron transfer step was the rate-determining step in the potential range from 0.3 to 0.6 V vs. RHE. An isotope exchange study performed to elucidate the mechanism unequivocally indicated the C-H bond cleavage was the rate-determining step. The number of electrons transferred increased gradually with the applied electrode potential, evidencing a change in the MOR mechanism, from the indirect pathway to the direct pathway involving the formation of adsorbed CO intermediate. The apparent methanol diffusion coefficient was evaluated using chronoamperometry and was found to be 5.37 × 10 −12 cm 2 /s −6 orders of magnitude lower than literature values for methanol/acid solutions. However, this value was deemed to be accurate as it yielded much more accurate estimations of the number of electrons transferred. A thin film diffusion model, involving the counter diffusion of gaseous CO 2 and other intermediates in a thin film adjacent to the electrode surface, was proposed to explain the observed methanol diffusion coefficient.

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