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S. Biswas, S. Barth, J. Holmes:
"Tailoring the Growth and Morphology of Germanium Nanowires in Supercritical fluid";
Talk: 3rd International Solvothermal and Hydrothermal Association Conference, Austin, Texas, USA; 2013-01-13 - 2013-01-17; in: "ISHA 2013 - Abstract & Program Book", (2013), 7-2.

Germanium nanowires have been successfully synthesized from a variety of supercritical fluid (SCF) methods, including supercritical fluid-liquid-solid (SFLS) and supercritical fluid-solid-solid (SFSS) approaches. The use of bi-metallic alloy seeds for growing one-dimensional nanostructures has recently gained momentum amongst researchers. The compositional flexibility of alloys provides the opportunity to manipulate the chemical environment, reaction kinetics and thermodynamic behavior of nanowire growth, in both the eutectic and sub-eutectic regimes. This presentation highlights the role of AuxAg1-x alloy nanoparticles in defining the growth characteristics and crystal quality of solid-seeded Ge nanowires, via SCF growth processes. The enhanced diffusivity of Ge in the alloy seeds, compared to pure Ag seeds, and slow interparticle diffusion of the alloy nanoparticles, allows realization of high-aspect ratio nanowires with diameters below 10 nm, via a seeded bottom-up approach. Solid seeded techniques, using Ag and Ag rich alloy seeds also facilitated growth of diameter-controlled nanowires in the sub-10 nm growth regime. Futhermore, the alloyed solid seeds enabled control over the crystallinity of the Ge nanowires produced, through an epitaxial defect transfer process from the seeds to the nanowires.