Ultrasmall Single-Crystal Indium Antimonide Nanowires

We report the rational synthesis of ultrasmall indium antimonide (InSb) nanowires down to 4.5 nm diameter. To achieve uniform InSb nanowires, we designed and performed the synthesis via a vapor-liquid-solid growth mechanism, where monodispersed gold colloids were used as a catalyst. The growth was carried out in a home-built three-zone chemical vapor deposition system, which allows continuous tunability of respective indium and antimony vapor pressure via separate temperature control. Several parameters are important for achieving successful nanowire growth, including the use of catalysts and tuning of the V/III ratio. Scanning electron microscopy revealed that InSb nanowires had uniform diameters with lengths up to several micrometers, and their sizes were defined by gold nanoparticles. High-resolution transmission electron microscopy structural characterization showed that as-prepared InSb nanowires were single crystals elongating along the < 111 > direction, regardless of wire diameter. Their chemical compositions were characterized by Raman spectroscopy and electron energy loss spectroscopy. The ability to rationally prepare ultrasmall, single-crystal InSb nanowires opens up new opportunities for studying the size-associated fundamental properties and provides insights for potential nanodevice applications.