Figure 4: Microstructure characterization for bulk composite.
From: Graphene-copper composite with micro-layered grains and ultrahigh strength

(a) XRD patterns of 2.5 vol.% and 5 vol.% RGO-Cu composites (b) Photograph of RGO-Cu composite, (c) SEM image of deeply etched cross section of 5 vol.% RGO-Cu composite, (d) schematic model of RGO-Cu composite, and (e) TEM image of 5 vol.% RGO-Cu composite and the inset is a HRTEM image of the composite.