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Nanomaterials derived from silicon and germanium have demonstrated several desirable properties for a variety of materials applications, such as optoelectronics, spintronics, catalysis, and thermoelectrics. Currently, the synthetic library for the production of technologically relevant Group IV nanomaterials comprised of silicon–germanium alloys, metal-silicides, and metal germanides are extremely limited, particularly with regard to solution-phase approaches. The work presented in this dissertation demonstrates the expansion of existing protocols to produce a variety of new Group IV-based nanomaterials using solution-phase syntheses. For the first time, silicon–germanium alloy nanocrystals are produced from a solution-phase approach. In addition, a new, generalizable scheme for the production of a variety of metal germanide nanocrystals is demonstrated through the use of metal(0) precursors. This methodology is then adapted to existing electroless etching methodologies used to produce silicon nanowire arrays, leading to the production of heterostructured silicon/metal silicide nanowires.

The semiconducting silicides offer significant potential for use in optoelectronic devices. Full implementation of the materials, however, requires the ability to tailor the energy gap and band structure to permit the synthesis of heterojunctions. One promising approach is to alloy the silicides with Ge. As part of an investigation into the synthesis of semiconducting silicide heterostructures, a series of β-Fe(Si1−xGex)2 epilayer samples, with nominal alloy content in the range 0 < x < 0.15, have been prepared by molecular beam epitaxy on Si(100). I present results of the epitaxial and crystalline quality of the films, as determined by reflection high-energy electron diffraction, Rutherford backscattering spectroscopy, and double crystal x-ray diffraction, and of the band gap dependence on the alloy composition, as determined by Fourier transform infrared spectroscopy. A reduction in band gap was observed with increasing Ge content, in agreement with previous theoretical predictions. However Ge segregation was also observed in β-Fe(Si1−xGex)2 epilayers when x > 0.04. Osmium silicide films have been grown by molecular beam epitaxy on Si(100). The silicides have been grown using e-beam evaporation sources for both Os and Si onto Si(100) substrates at varying growth rates and temperatures ranging from 600-700ºC. The resulting films have been analyzed using reflection high-energy electron diffraction, Raman spectroscopy, reflectivity measurements, in-plane and out of plane X-ray diffraction and temperature dependent magnetotransport. A change in crystalline quality is observed with an increase in Si overpressure. For a lower silicon to osmium flux ration (JSi/JOs=1.5) both OsSi2 and Os2Si3 occur, whereas with a much larger Si overpressure (JSi/JOs>4), crystalline quality is greatly increased and only a single phase, Os2Si3, is present. The out-of-plane X-ray diffraction data show that the film grows along its [4 0 2] direction, with a good crystal quality as evidenced by the small FWHM in the rocking curve. The in-plane X-ray diffraction data show growth twins with perpendicular orientation to each other.