[Ifeffit] white line intensity v. edge position in determining oxidation state of Re

Bruce Ravel bravel at anl.gov
Thu May 17 15:36:29 CDT 2007


On Thursday 17 May 2007, Edward L. Kunkes wrote:
>  I am trying to determine the oxidation state of Re in PtRe nanoparticles
> catalysts supported on carbon. The ReLIII edge was measured before and
> after an in-situ reduction in hydrogen. Can anyone suggest Which
> characteristic of the edge is more related to oxidation state ? Is it the
> integrated white-line intensity or the position of the edge(point of
> maximum derivative). The edge position of the ReLIII edge of my particles
> is the same as that of Re foil, however the white line instensity is
> significanty higher. For the non-reduced PtRe particles, the edge position
> is similar to that of ReO2 (with a larger white line intensity).

I see that no one has responded to this, so I'll take a stab.

Presumably you know what the end members -- Re metal and Re oxide --
look like.  Can you do linear combination fitting of the intermediate
spectra to determine the average oxidation?

B


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 Bruce Ravel  ---------------------------------------------- bravel at anl.gov

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