Figure 1.

SEM cross-section images of (a) A30M3S, (b) A30M6S, (c) A30M10S, (d) A5M3S and (e) A5M6S. Silver aggregates grow mainly at the SiNWs tips, and only a few silver nanoparticles may decorate the nanowire walls for the longer SiNWs. The aggregates increase in size with increasing re-immersion time in the MACE solution. Top view SEM images showing the top surface of (f) A30M3S, (g) A5M3S, (h) SEM image after removing the Ag aggregates from A5M3S, (i) EDS spectrum obtained from an area of (g).