Plasmonic metasurfaces are leading the development of next-generation optical devices with unprecedented compactness and functionality. In contrast to bulk refractive optics, these planar surfaces manipulate light with rationally designed subwavelength building blocks. This thesis focus on how emerging materials and design methods advance the eld of metasurfaces. Chapter 1 reviews...
Organic semiconductors are an active area of research with great promise for delivering next generation electronics and clean energy technologies. As the field matures, understanding the connection between molecular structure, materials’ properties, and device performance will be critical in finding the right material for an intended application. An effective strategy...
Increasing industrialization and the resulting negative environmental impacts highlight the need to develop alternative renewable energy sources. The Sun is a massive source and organic solar cells are a growing field of study. As new materials are synthesized, the efficiencies of organic solar cells continue to grow, but without an...
One of the grand challenges in materials chemistry and nanochemistry is the development of functional materials through ordered, hierarchical structures using synthetic building blocks. Nature has done this through evolution of molecular components such as nucleic acids, saccharides, lipids, amino acids, and inorganic crystals. The precise spatial positioning of these...
This thesis centers around the development and application of novel high throughput lithography tools. These advances help: 1) establish the field of nanocombinatorics, where massive libraries (termed megalibraries) of materials can be prepared in a positionally encoded manner and then screened for functional activity, and 2) advance stereolithographic 3D printing...
Functional electronic materials are difficult to design due to the complex interplay among chemistry, atomic structure, and electrical properties. This dilemma is further amplified in transition metal compounds which can defy the band-theory description of non-correlated electrons. Exploring the vast possible design space completely with experiments or first-principles simulations is...
Biomaterials have immense potential for studying fundamental biological processes and developing therapies to help regenerate or replace the structure and function of injured tissues. In order to accomplish this, they need to be designed to mimic the structure and function of Nature’s most important material, the extracellular matrix (ECM) surrounding...
The dissertation systematically delineates the mechanically-guided deterministic assembly of three-dimensional (3D) mesostructures by compressive buckling, covering topics from mechanics concepts, design and analysis, fabrication techniques, to application opportunities. The development of approaches to form complex 3D functional mesostructures in advanced materials is a topic of broad interest, thanks to the...
SAMDI-MS (Self-Assembled Monolayers for MALDI-TOF Mass Spectrometry) couples the use of chemically-defined self-assembled monolayers of alkane thiolates on gold surfaces with MALDI-TOF mass spectrometry for rapid characterization of the surfaces. Reactions performed on the surfaces can be quantified directly by detection of the reaction substrates and products. This rapid detection...
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...
Colloidal crystal engineering with DNA offers new opportunities for materials scientists to build and program the structures of superlattices beyond what can be accomplished in Nature with atomic crystal lattices. Thus far, such materials primarily have been studied for their optical properties due to the insulating nature of the DNA...
The heart of computational materials science lies in providing fundamental insights and understanding of materials behavior and properties across different scales. The significance of this task is highlighted by the Materials Genome Initiative and the emergence of computational tools and frameworks such as materials by design, microstructure sensitive design, and...
Nucleic acids not only are the building blocks of life but also a class of attractive macromolecular therapeutics. However, the delivery of therapeutic oligonucleotides into cells has been a major challenge due to their large size and highly negatively charged backbone. Spherical nucleic acids (SNAs) are a class of emerging...
Non-covalent and ion-specific interactions in the context of charged polymers are ubiquitous in nature and in synthetic applications. For example, mussels utilize metal-coordinate bonds to form tough underwater adhesion to a wide range of substrates. The sandcastle worm uses coacervation of oppositely charged polymers to build robust structures for self-defense....
To relate the mechanical responses of hard-soft copolymer systems with their microstructures, a coarse-grained molecular dynamics (CGMD) approach is employed. With the generic bead-spring polymer model mapped from atomistic simulations, this dissertation first studies the morphology of structures with various hard-soft compositions and interactions between hard beads. Following that, this...
The start of the 21st century brought the sweeping proliferation of portable electronics such as laptops, tablets, and smartphones. These technologies were largely enabled by advances in energy storage methods – lithium ion batteries in particular. Society's push for more advanced energy storage applications, such as electric vehicles, stresses the...
Two-dimensional (2D) materials are a promising class of electronic materials that have generated great interest to improve and create new and existing technologies. The promise of this family of materials relies on their high surface-to-volume ratio and atomic thickness in addition to their unique (opto)electric properties. However, these morphological properties...
In the United States and around the world, the growing energy demands and climate concerns necessitate renewable and efficient energy production. Thermoelectric materials could be one small part of this larger picture movement, but their high cost and low efficiency must be improved to realize commercial use. To decrease the...
Soft materials such as colloids and polymers often exhibit a variety of mesoscopic structures that are governed merely by weak physical interactions. Due to these intermediate structures, they can be easily taken out of thermal equilibrium by introducing external stimuli such as a shear flow and electromagnetic fields. This thesis...
One of the grand challenges in science is development of soft materials that mimic living organisms to optimize the way we use energy, translate or morph reversibly or sense their envi- ronment and respond in a useful fashion. Using the insights from studying biological structures, we hope to design soft...
Ultrafine particles are often used as lubricant additives because they can enter tribological contacts to reduce friction and protect surfaces from wear. They tend to be more stable than molecular additives under high thermal and mechanical stresses during rubbing. However, in lubricant oil, ultrafine particles tend to aggregate together to...
The halide perovskites AMX3 (A = large cation, B = Sn or Pb, and X = halide) have been the subject of intense investigation due to their outstanding optical and electronic properties, which have enabled high solar cell efficiencies thanks to a beneficial electronic structure and long charge carrier lifetimes....
Rationally assembled nanostructures exhibit distinct physical and chemical properties beyond their individual units. The development of nanofabrication tools enables precise structural defining of nanomaterials scalable to large areas. This dissertation focuses on plasmonic nanoparticle arrays that show unique diffractive coupling with lattice spacings engineered close to the wavelength of light....
Transport along and across the grain boundaries of solid-state electrolytes has implications for a broad range of materials and in an equally broad range of technologies. Over the past 2-3 decades, a substantial body of literature has been developed to explain grain boundary transport properties within the context of space...
Additive manufacturing is a promising process that has the capability to build components with complex geometries for structural and biomedical applications. Due to the rapid and localized directional solidification of molten metallic alloys, unique phase transformations occur at the melt pool that can provide for components with greater strength and...
This thesis describes a series of fundamental studies that address the role of electrostatic interactions in modulating i) the permeability of the ligand shell of a colloidal quantum dot (QD) to an anionic redox probe; ii) the resulting yield of photoinduced electron exchange within the QD ‒ redox probe complex;...
Rapid changes in global climate are pushing nations to reduce CO2 emissions and adopt clean energy technologies for renewable energy generation and storage. As wind and solar are implemented worldwide, a commensurate response in energy storage will need to be installed to meet fluctuations in peak energy demands and generation...