Figure 4

Growth of GNR/CNT junctions. (a) Schematic of growth of GNR/CNT junctions through abrupt change of H2 pressure. The product switches from ribbon to tube, which yields a junction structure in the middle. (b) Topography of a typical GNR/CNT junction structure. (c) A zoom-in AFM image of the joint region in the dashed box in panel (b). Height profiles taken along the dashed lines show the tube height ~ 0.7 nm and ribbon height ~ 0.2 nm. Scale bars: 200 nm in (b); 100 nm in (c).