In composite material, two elements of the base material show a positive shift in the binding energy, while the third element shows a negative shift in the binding energy.
What are the reasons for this?
Thank you.
Since you didn't give any additional specifications, rules of thumb are:
higher binding energy -> electron density was withdrawn from the element by the surrounding
lower binding energy -> the element has withdrawn electron density from a counterelement
I think that the peak shift of the core electron reflects the localization of valence electrons between the two bonding atoms. Therefore, from a simple perspective, it is reasonable to assume that some kind of electron localization occurs due to the interaction between the added third component and the two originally existing components. To be more precise, it is necessary to confirm which peak of what compound is being viewed.