XPS photoemission in carbonaceous materials: A “defect” peak beside the graphitic asymmetric peak

When following by XPS the evolution of a series of graphitic materials submitted to either mechanical, chemical or thermal treatment, the addition of a “defect peak” to the classical pristine asymmetric line appears imperative in the fitting. This new peak is broader than and very slightly shifted from the graphitic peak. Its intensity depends on the consequence of the treatment: creating or destroying the crystalline/molecular order. It may be in confidence attributed to carbon atoms located in defective regions and surely out of sp2 graphitic configuration. Fitting the C 1s XPS spectrum in such a way is proven to be accurate during graphitization of anthracene semi-cokes and during milling of graphite powders under different atmospheres.