Chemical Bonding Elucidation of Graphene Films Synthesized by Low Temperature CVD-Growth

<title>Abstract</title> <p> The grapheme was layers synthesized via chemical vapor deposition (CVD) utilizing a carbon source from a polymer film matrix with an organic solvent. In particular, the carbon (C) source for CVD synthesized graphene was chlorobenzene solvent in a poly(methylmethacrylate) (PMMA) matrix. The catalytically deposited multi-layered graphene on copper foil (Cu) was characterized by Raman spectroscopy. X-ray photoelectron spectroscopy (XPS) was used to analyze the bonding environment over large areas of the graphene sheet on the copper foil after growth. This analysis revealed the bond energy of C and contributions of other elemental species. The second most abundant element after carbon was found to be oxygen (O) atoms. This observation is related to the problem of removing all the O species from the surface of the catalyst in the cleaning process. One of the key results is that the energy binding of the level C 1s in a sp ² structure is about 284.3 eV. The carbon sp3 core level peak is found at 284.9 eV. It is significant and indicates the grapheme presence. Further tests, including near-edge X-ray absorption spectroscopy (NEXAFS), verified the presence of C atoms. The NEXAFS data was providing better bonding information and variation of electronic structure of the carbon layers as a function of growth temperature (T _growth ) was observed. </p>