Abstract
Phase changes between PdO and Pd metal can be directly detected in PdO/CeO2 catalysts supported on χ-Al2O3 by means of in situ high-temperature measurements of X-ray diffraction and FT-IR in relation to the catalytic activity for the methane oxidation of microcrystalline PdO. Reversible changes in the solid phases are observed from PdO to Pd and Pd to PdO under O2-deficient and O2-excess atmospheres, respectively. Nanosizes of PdO and Pd crystallites, the distorted PdO crystal structure along the (110) plane, and also a distorted Pd metal crystal structure along the (200) plane as well as the large surface area elucidate the high catalytic activity for the methane oxidation of PdO/CeO2 catalysts prepared with an atomic ratio of Pd:Ce = 1:1.
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References
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Kanezaki, E., Tanaka, S., Murai, Ki. et al. Direct Detection of a Phase Change in PdO/CeO2 Supported on χ-Al2O3 by Means of in situ High-Temperature Measurements of XRD and FTIR. ANAL. SCI. 20, 1069–1073 (2004). https://doi.org/10.2116/analsci.20.1069
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DOI: https://doi.org/10.2116/analsci.20.1069