Figure 3.
SEM image of the Au coated carbon nanotube nanoneedle. (a) Carbon nanotube nanoneedle before Au nanoparticle coating and (b) after Au nanoparticle coating (scale bar: 5 μm). (c) Magnified view of Au nanoparticle-coated nanoneedle (scale bar: 200 nm). (d) EDS spectrum of Au nanoparticle-coated nanoneedle.