Date of Award
Doctor of Philosophy
Kirill . Kovnir
Elemental P and As crystallize in layered structures; exfoliation of these structures using tape gave rise to novel 2D materials, phosphorene and arsenene. When pnictogens, such as P and As, are combined with light tetrels, Si and Ge, the resulting binary compounds are layered van der Waals materials. Strong covalent tetrel-pnictide bonding is found within the layer, while weak van der Waals type interactions are found between the layers. Strongly anisotropic bonding makes such materials not only easy to exfoliate but also stable against oxidation, unlike phosphorene-like materials. Strongly anisotropic and fascinating properties were predicted computationally and observed experimentally for this class of materials and their individual layers. Tetrel pnictides have been shown to have several promising applications which include thermoelectrics, batteries, photovoltaics, optics, and superconductivity. To further expand the boundary of known tetrel pnictide systems and their characterization, a deeper understanding of their synthesis and crystal growth is required. Solid state synthesis involving elements, binary precursors, and metal flux has yielded several novel tetrel pnictide phases, which exhibit complex and unique structural motifs, inherently influencing their physical properties. These phases can span the full range of 0D to 3D structures. Further complexity can be added to these structures through doping of framework atoms or cations in the layers, allowing for the tuning of desired properties, making tetrel pnictide systems extremely versatile for materials applications. In this work we specifically focus on the synthesis and characterization of binary and ternary tetrel pnictides containing Si, Ge, P, and As.
Mark, Justin, "Structural diversity and characterization of novel tetrel pnictides" (2019). Graduate Theses and Dissertations. 17739.
Available for download on Thursday, November 25, 2021