Raman spectra of C SP2 and C SP3 in C:SiOxfilm. It confirms the existence of graphene oxide. The upper inset is the corresponding FTIR spectra, from which graphene oxide coupling OH peak can be observed at the wavenumber of 3,665 cm-1.
Zhang et al. Nanoscale Research Letters 2013 8:497 doi:10.1186/1556-276X-8-497