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For the purpose of lowering the sintering temperature of alumina with a CuO-TiO₂-Nb₂O₅ additive, effects induced by changes in the firing atmosphere, in particular, oxygen partial pressure (pO₂), were studied. It was confirmed that sintering was promoted in regions where the pO₂ was lower than that in the air atmosphere, 0.21 atm. Our analysis of the additive using TG-DTA and XRD methods indicated that both the melting temperature and compositions of the produced compound vary with the change in firing atmosphere. These changes were presumed to affect the sintering performance. By lowering the pO₂ to 0.05 atm, a dense sintered sample with good dielectric properties was obtained at a firing temperature of 925 °C.

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For the direct formic acid fuel cells, anodic Pd catalyst has attracted considerable attention recently. In order to enhance the catalytic ability, conductivity, and prevent from the catalyst poisoning, the synthesis of Au-Pd solid solution phase decorated on Ir or Ru doped CeO₂ modified MWCNTs substrate by polyol and synchrotron X-ray irradiation method were studied. The composition, structure and morphology were analyzed by XRD, SEM, TEM, TGA, and ICP, respectively. The hybrid AuPd/MOS/MWCNTs were not formed a single phase of AuPd in EG solution via polyol method but successfully synthesized in DI water solution by X-ray irradiation photochemical method at beam line 01A in Taiwan synchrotron radiation research center. The electrochemical analysis of AuPd series electrocatalysts via polyol method, AuPd/Ru_xCe_1−xO₂/MWCNTs have the highest electro-oxidizing current density in cyclic voltammetry experiment. However, Pd/CeO₂/MWCNTs have the lowest potential in the maximum electro-oxidizing current density. The results of ECSA indicate the AuPd/Ru_xCe_1−xO₂/MWCNTs have the highest electrocatalytic property. For the electrocatalysts synthesized via X-ray irradiation method (1A), AuPd/MWCNTs (1A) has the highest electro-oxidizing current density in cyclic voltammetry experiment meanwhile it has the lowest potential in the maximum electro-oxidizing current density. In addition, the results of ECSA indicate the AuPd/CeO₂/MWCNTs (1A) have the highest electrocatalytic property which AuPd/MWCNTs is almost matched with. Also, the results indicate Pd/CeO₂/MWCNTs (polyol) have the highest stability up to 10 k seconds with 250 mA/mg Pd current density.

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