A fundamental materials science question is “why and how will this material form?” The experimental,computation, and time resources necessary to answer this question consume significant resources due to the
predominantly trial-and-error based approaches common in materials research. This dissertation reintroduces
a number of fundamental thermodynamics-based tools for the study of...
Renewable energy technology, more so than ever before, is critical to the survival of humanity. For decades, concentrated efforts into designing and developing such novel devices resulted in the innovation of solar-driven photovoltaics that were competitive with nonrenewable alternatives. This thesis explores the dynamic behavior of alternative material candidates that...
Engineering responses of soft materials at hierarchical time and length scales is of great interest to both fundamental science and technological applications. In recent years, the hybridization between emerging soft condense matters and conventional hard condense matters keeps enriching the materials library of humankind and opens another largely-uncharted venue for...
The effect of interfaces in solids on the overall charge transport properties has become a topic of growing importance for energy materials such as thermoelectrics. In some polycrystalline thermoelectric materials, the performance near room temperature is significantly limited due to thermally-activated electrical conductivity near room-temperature, which can be attributed to...
Given directives such as the UN Global Goals targeting sustainable development, the research presented herein makes but a small contribution to the advancement of alternative energy technologies. Nevertheless, the present work was largely motivated to address specific points of intrigue within the thermoelectrics community. The general principles demonstrated, however, may...
Interfacial science brings together diverse areas of interest such as electronic materials, quantum materials, bio-membranes and catalysts. In-situ X-ray characterization techniques can be used to understand the assembly of atoms, molecules and supported nanoparticles at interfaces in complex environments. This thesis work focuses on the use of various X-ray characterization...
Electrostatic interactions mediated by ionic environments play a central role in physical processes across materials science, chemistry and biology. Key biological phenomena, such as the condensation and packaging of DNA, ion transport across cellular membranes and the enzymatic action of proteins, rely on the complex interplay between nanoscale electrostatic, osmotic...
Metallic conductivity and broken inversion symmetry were long thought to be contraindicated properties, under the assumption that long-range Coulombic interactions (screened by free charge carriers) were necessary for coordinated polar displacements. Within the past decade, the discovery of polar metals has prompted a rethinking of the relationship between metallicity and...
This thesis describes the synthesis and photophysical characterization of low-dimensionalmaterials—including thin-film semiconductors, colloidal quantum dots, and molecules—with the
broader motivation of integrating them into mixed-dimensional heterostructures with novel
responses to external stimuli. Due to their high surface area to volume ratio and incomplete
dielectric screening, mixed-dimensional heterostructures have high sensitivity...
From the early usage of metallic thin films as mirrors tracing back to 2900 BC, to the modern thin film photonic circuits as a mature optical processing platform, and to the growing class of atomically-thin two-dimensional (2D) materials with diverse and tailorable properties, thin film materials have played an important...
In this dissertation, I summarize my findings of the dynamics of colloidal suspensions over a large range of volume fractions in two systems: drop impact and film rupture. The existence of a deformable surface in both these systems allows me to capture the consequences of non-Newtonian flow using high-speed imaging....
How molecular chirality manifests at the nano- to macroscale has been a scientific puzzle since Louis Pasteur discovered biochirality. In general, amphiphilic molecules can organize into a variety of assembly shapes including micelles, spherical vesicles, cylindrical micelles, and planar bilayers. However, when such amphiphilic molecules are chiral, helical ribbons, helicoidal...
The three-dimensional (3D) nanoscale structure of III-As nanowires is correlated with optical and electronic property measurements to deconvolve the contributions of strain, composition, and crystal structure to characteristics of interest for future electronic and optoelectronic devices. Multiple advanced two-dimensional (2D) and 3D characterization techniques are employed such as atom probe...
This dissertation explores the fundamental science of flexoelectricity and its implications using a combined experimental and theoretical approach. I begin by introducing the flexoelectric effect and formalizing the basics of strain gradients, polarization, and flexoelectric coefficients. Next, I describe the development of a flexoelectric characterization system based upon three-point bending...
Engineering heat transport in materials is essential for thermal management in a wide range of technologies, from batteries to thermoelectrics. Materials host a wide spectrum of heat-carrying phonons, which vary in their frequency, spatial extent, and degree of plane-wave character. This diversity in phonon properties leads to complex behavior, especially...
