High-resolution electron energy-loss measurements of sticking coefficients of methane decomposition on Ru( 0001)
نویسندگان
چکیده
A new approach, utilizing an elevated pressure reactor and high-resolution electron energy loss spectroscopy (HREELS), to the measurement of sticking coefficients of methane decomposition on Ru(0001) has been demonstrated. It has been shown that the detection, by Auger electron spectroscopy and photoelectron spectroscopy, of fractional monolayers of carbon on ruthenium is difficult because of the interference of the substrate signals. HREELS thus offers new opportunities to measure carbon buildup kinetics on ruthenium crystals. The measured initial sticking coefficient for methane decomposition on Ru(0001) varies from 1.7-12.7 X lo-’ in the 500-650 K temperature range. The apparent activation energy for methane dissociation is found to be 8.5 kcal/mol.
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