Diameter Control of GaSb Nanowires Revealed by In Situ Environmental Transmission Electron Microscopy.

Several nanowire properties are strongly dependent on their diameter, which is notoriously difficult to control for III-Sb nanowires compared with other III-V nanowires. Herein environmental transmission electron microscopy is utilized to study the growth of Au nanoparticle seeded GaSb nanowires in situ . In this study, the real time changes to morphology and nanoparticle composition as a result of precursor V/III ratio are investigated. For a wide range of the growth parameters, it is observed that decreasing the V/III ratio increases the nanoparticle volume through Ga accumulation in the nanoparticle. The increase in nanoparticle volume in turn forces the nanowire diameter to expand. The effect of the V/III ratio on diameter allows the engineering of diameter modulated nanowires, where the modulation persisted after the growth. Lastly, this study demonstrates the observed trends can be reproduced in a conventional ex situ system, highlighting the transferability and importance of the results obtained in situ .