Figure 1

Mapping and atomic-resolution imaging of atomic steps on the free-standing few-layer reduced graphene.

(a), Atomic step mapping on the BF STEM images. (b), Identification of layer numbers on the HAADF STEM image for (a). (c), Atomic-resolution imaging of one monatomic step between the bilayer and trilayer graphene indicated by white arrows in (a) and (b) using BF STEM. (d), The image from (c) with the atomic step area at top layer outlined. (e), HAADF STEM images of one monatomic step. Red arrow indicates adatoms at step edges. (f), The image from (e) with the atomic step area at top layer outlined. Scale bars in (a), (b), 1 nm; scale bars in (c–f), 0.5 nm. (a) and (c–f) are low-pass-filtered images to remove noise. Green line, atomic steps between single layer (I) and bilayer (II). Red line, atomic steps between bilayer (II) and three layer (III). Brown line, atomic steps between three layer (III) and four layer (IV). Blue line, atomic steps between bilayer (II) and four layer (IV). Purple line, atomic steps between single layer (I) and three layer (III). Black line, atomic steps between single layer (I) and four layer (IV).