Figure 1.

a and b show the Au–Zn clusters with the nucleation sites formed on the substrates. c Early stage of nanowire nucleation from the Au–Zn clusters. d and e show eventual wire formation with the presence of the catalyst at the nanowire tip (also shown as inset in fig e). Scales in figure (a), (d), and (e) are 2 μm, whereas in figures (b) and (c), the scale is 500 nm and 200 nm, respectively.