CO adsorption on Pd( 111): the effects of temperature and pressure
نویسندگان
چکیده
Infrared reflection-absorption spectroscopy (IRAS) has been used to study the adsorption of carbon monoxide on a Pd(ll1) surface. IRAS spectra were collected at temperatures from 100 to 1000 K and at pressures from 1.0 x lo-’ to 10.0 Torr. The IRAS data at temperatures > 250 K showed the coverage versus temperature behavior anticipated from the data acquired under UHV conditions. However, at temperatures < 250 K, multiple CO adsorption structures were observed which were dependent upon the adsorption temperature and pressure. The low temperature/ low pressure adsorption data extrapolate to the high temperature/ high pressure regime only if appropriate adsorption conditions are employed.
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