  A simple method is developed to synthesize gram quantities of uniform Ge
nanowires (GeNWs) by chemical vapor deposition on preformed, monodispersed
seed-particles loaded onto high surface area silica support. Various chemical
functionalization schemes are investigated to passivate the GeNW surfaces using
alkanethiols and alkyl Grignard reactions. The stability of functionalization
against oxidation of germanium for various alkyl chain lengths is elucidated by
X-ray photoelectron spectroscopy. Among all schemes tested, long chain
alkanethiols (>=C12) are found to impart the most stable GeNW passivation
against oxidation upon extended exposure to ambient air. Further, the
chemically functionalized oxidation-resistant nanowires are soluble in organic
solvents and can be readily assembled into close-packed Langmuir-Blodgett films
potentially useful for future high performance electronic devices.
