High-pressure torsion (HPT) is an effective severe plastic deformation (SPD)
technique to produce bulk nanostructured materials (BNMs). These BNMs often show a combination of exceptional mechanical and physical properties. Processing of single metals and alloys by HPT has been understood that the homogenous microstructures can be achieved throughout the disk...
Understanding the impact of inter-molecular orientation on the optical proper-ties of organic semiconductors is important for designing next-generation organic (opto)electronic and photonic devices. However, fundamental aspects of how various features of molecular packing in crystalline systems determine the nature and dynamics of excitons have been a subject of debate. Toward...
Uranyl peroxide clusters are the newest family of polyoxometalates, discovered in 2015. Although this family is new, over 70 topologies have been reported. However, we lack the fundamental understanding of assembly mechanisms, particularly the role of the alkali countercations. Here, we use a wide range of solution and solid-state characterization...
Understanding structural evolution in solids as composition changes is essential to materials properties prediction. Such structure-properties relationships are the theme of solid state chemistry. Materials scientists and chemists have utilized an abundance of simple crystal structures to enhance understanding of chemical and structural origins of properties in materials for decades....
The electrical grid is a key component of the Nation's critical infrastructure. Its continuous and reliable operation is of vital importance; any system-wide disruption would have a debilitating impact on crucial services, public health and safety, the economy, and the national security of the United States.
High-impact low-frequency events pose...
Generation resources are shifting from centralized, high inertial, fossil fuel based to decentralized, no inertia, and variable renewable resources. The evolution of generation resources in electrical grids requires the transformation of the electrical grid infrastructure, and operation and planning procedures and standards. This dissertation takes four investigations into how to...
Aluminum and copper and their alloys have been widely used due to relatively high strength-to-weight ratios compared with conventional steels. Processing of these alloys is typically conducted at high temperatures over extended time periods. High-pressure torsion (HPT) is a promising processing technique for introducing significant grain refinement leading to excellent...
This work explores the synthesis and characterization of the metastable alloys Sn1-xCaxCh (Ch= S, Se) and nitride compounds Zn-W-Mo-N, which have recently been predicted by theorists. Single phase thin films of Sn1-xCaxS are prepared by pulsed laser deposition and radio-frequency magnetron sputtering and of Sn1-xCaxSe are prepared by pulsed laser...
Metal oxide nanoparticles (MONPs) are manufactured at the greatest rate of any class of nanomaterial due to their wide variety of industrial, commercial, and environmental applications. The sustainable use of MONPs requires a balance of careful consideration of their potential negative environmental impacts with the effective exploitation of their unique...
Structure-specific synthesis processes are of key importance to the growth of polymorphic functional compounds such as TiO₂, where material properties strongly depend on structure as well as chemistry. The robust growth of the brookite polymorph of TiO₂, a promising photocatalyst, has been difficult in both powder and thin-film forms due...