AFM and KPFM measurements were recorded on a Bruker MultiMode 8 AFM instrument. For KPFM measurements, the SCM-PIT-V2 probe was used and calibrated with a standard sample of HOPG. XPS data were obtained on an Axis Supra instrument (Kratos Analytical) using the monochromated K X-ray line of an aluminum anode. Synchrotron GIXRD data were obtained at beamline BM01, Swiss-Norwegian beamline (SNBL), at the European Synchrotron Radiation Facility (ESRF) at wavelengths of 1.04157 Å , data analysis was with the tools developed at the beamline as discussed in the previous work(71) (For details, see Supplementary Note 4).