Measurement of the relative abundance of sp2 and sp3 hybridised atoms in carbon based materials by XPS: a critical approach. Part I

A few of the approaches put forward to measure the fraction of sp2 and sp3 hybridised carbons in carbon systems via photon excited electron spectroscopies are compared. To test the various methods, synthesised (part I of the work) and real non synthesised spectra, (part II) were used. The first were generated as linear combinations of the spectra of polycrystalline diamond and graphite. Reasonable results are found, at least within the assumptions at the basis of the present work. Methods based on spectral fitting are generally superior to others provided the relevant spectral region is carefully chosen and the fitting procedure is well specified