Time-Resolved DXAFS Study of Adsorption and Release of Hydrogen on Pt /MCM-41
نویسندگان
چکیده
We have clarified the adsorption and release mechanism of hydrogen to/from Pt clusters on an MCM-41 surface by using the XAFS technique. After reduction, the icosahedral Pt13 cluster of r(Pt-Pt) =0.273 nm is formed. In contrast, a very small oxidized metal particle of r(Pt-Pt) = 0.254 nm is formed after the oxidation. We have measured time-resolved energy dispersive XAFS in order to clarify the adsorption and release mechanism of hydrogen to/from Pt clusters on an MCM-41 surface. Although the reduction process can be explained as the sum of the initial and the final species, a third species should be considered in the oxidation process.
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