Separation of C K-NEXAFS spectra for layer-by-layer analysis of carbon-based thin films: An n-alkane monolayer adsorbed on a monolayer graphene substrate grown on a Pt(1Â 1Â 1) surface

Spectral separation methods for X-ray absorption fine structure spectroscopy at the near carbon K-edge are examined for an n-C36H74 monolayer adsorbed on a monolayer graphene grown on a Pt(1 1 1) surface. The spectra of n-C36H74 and the monolayer graphene are separated by fitting decay curves obtained for all photon energies by detecting photoelectrons as a function of the ejection angle. The results are discussed in comparison with separation results obtained by subtracting the independently measured graphene spectra as a background.