(a), High-resolution TEM (HRTEM) image taken at the edge of a LIG flake showing few-layer features and highly-wrinkled structures; scale bar, 10 nm. (b), HRTEM image of LIG; scale bar, 5 nm. Average lattice space of ~3.4 Å corresponds to the (002) planes of graphitic materials. (c), Cs-STEM image taken at the edge of a LIG flake; scale bar, 2 nm. It shows an ultra-polycrystalline nature with grain boundaries. (d), TEM image of selected area indicated as a rectangle in (c). It shows a heptagon with two pentagons, as well as a hexagon; scale bar, 5 Å.