Fundamental and in situ Microscopy Studies of III-V Nanoscale Wires and Particles
In this work, I first demonstrate the synthesis of ternary III-V alloy (e.g., InPSb) nanowires via self-catalyzed vapor-liquid-solid (VLS) growth techniques using indium catalyst, which then promotes inquiry into the physical properties of a similar catalyst seed material (e.g., gallium) in an effort to elucidate key parameters for potentially tuning particle size, and consequently wire size. Understanding the behavior of group III metals such as droplets provides fundamental insight into liquid-catalyzed nanowire growth. Mechanistic insight on gallium droplet growth and evaporation kinetics is ascertained by systematic variation of parameters coupled with the use of powerful techniques such as in situ transmission electron microscopy (TEM) and focused ion beam (FIB) milling. Observing the kinetics of pure gallium in contrast with gallium containing a native oxide shell, in addition to growth and diffusion studies of gallium droplets, facilitates knowledge integration towards an interconnected development continuum route as proposed by the Materials Genome Initiative (MGI). Herein, I demonstrate the integration of synthetic and analytical techniques to synergistically form the basis towards obtaining a general, fundamental understanding of particle growth systems. Obtaining a mechanistic understanding of particle evolution/devolution by synergistically employing computational and analytical methods will advance nanotechnology and materials science by promoting a drive towards the intuitive design of next-generation, application-specific materials with enhanced properties for future applications, rather than relying on their serendipitous discovery through trial and error.