The NPG film formed on the different facets after 500 ms is shown in Fig. , where Figs. and show the regions vicinal to the Au(111) and Au(100) facets and Figs. 8c to f the flat Au(111) and Au(100) regions (low index regions). According to Fig. the NPG film starts to exfoliate from the Au(111*) facet, while on the Au(100*) facet in Fig. the NPG film tends to be more stable/homogeneous with a small number of defects, such as the one in the center of the image. The NPG film on the Au(111) and Au(100) facets also exfoliates strongly, as shown in Figs. 8c to f. Overall, on the Au(100) facet, the exfoliation is more pronounced in certain regions than others. This aspect might be due to an inhomogeneity in the local atomic structure on the (100) facets. However, such detailed atomic insights can not be inferred from SEM imaging and require further studies on oriented single crystals.