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¡ï ¡ï mkingl(½ð±Ò+1): лл²ÎÓë missu001: ½ð±Ò+1, ¸Ðл½»Á÷ 2013-05-23 08:30:22
Dispersion, % = (No. Surface Atoms / Total No. Atoms) x 100
When using supported metal catalysts, there are several molecules that can be selected to use as adsorbates. These include carbon monoxide, oxygen, hydrogen and nitric oxide. In all these cases, it is important to know:
• What is the metal atom to adsorbate gas stoichiometry?
• Does the molecule adsorb associatively or dissociatively?
• Does the support material play any part in the adsorption, i.e. is there spillover, or does the support play an active role in adsorption?
In order to calculate the metal dispersion, the ratio of adsorbate gas to metal sites must be known. |
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