Plasmonic nanomaterials have been the subject of an increasing amount of research interest due to the unique light-harvesting properties of localized surface plasmon resonances. However, the common noble metals used – Au, Ag, and Cu – have high costs and low abundance, making larger scale applications prohibitive. Research into alternative plasmonic materials focuses on the more bountiful Al and Mg as supplements to existing materials. However, synthesis of Al and Mg nanocrystals has historically been challenging, as they are highly oxophilic, requiring O2 and H2O-free environments. Furthermore, the reduction potentials of these metals are so negative that they have traditionally been used as reducing agents within chemical reactions. The first part of this thesis presents work that focused on developing our understanding of Al nanocrystal growth and expanding our repertoire of particles shaped through use of transition-metal catalysts. To this end, initial studies focused on spectroscopic evidence of several Ti-based cyclopentadienyl molecules acting not only as catalysts for the reduction of Al precursor species to Al0, but also as capping agents present on the surface of our grown crystals. This has allowed us to propose a mechanism for the growth of Al{100} and {111}-terminated nanoparticles, guiding future catalyst design. Additionally, extensive work born of our knowledge on catalyst-binding yielded growth of reduced-dimensionality Al particles. Through targeted catalyst design, we were able to grow crystalline Al nanoparticles from bars to nanowires, and even into two-dimensional nanoparticles such as twinned 2D Al nanodiamonds. This is accomplished through modification of the binding strength between the Al precursor and reduction catalyst. We then probe the ability of the Al nanowires as waveguides through extensive optical and electronic characterization. The wires hybridize with plasmonic Au films of various thicknesses and reveal more insight into the physical processes of plasmon hybridization. The wires also demonstrate remote excitation and detection of coupled visible-light emitting particles, paving the way for future air-stable plasmonic waveguiding devices. Concurrently, the last chapter in this thesis focuses on using our Al nanomaterials as catalysts themselves in organic chemical solution-phase reactions. Al NCs converted light into electrons through the excitation of ballistic hot electrons, which were ejected into the surrounding solvent. This process formed solvated electrons, characterized by a long-lived lifetime well beyond the ultrafast timescale of hot carriers. Their reactivity was harnessed with a spin-trap and a radical cyclization reaction. These plasmonically-generated solvated electrons offered far more control over other traditional methods of generation and gave rise to reaction selectivities typically not expressed by the constituents. Finally, our solvated electrons have quantum yields of over 1.1%, demonstrating a functional avenue for synthetic chemists to use for reduction reactions.