Human skin oils are significant scavengers of atmospheric oxidants in occupied indoor environments. Many techniques used to study gas-phase transformations of surface films indoors have been limited to off-line bulk analysis, although more surface-selective methodologies are emerging. Here, we present a multi-prong analytical approach to characterizing skin oil ozonolysis. Skin...
Natural gas is likely to become one of the main sources of carbon-based chemicals in the next century due to rapidly increasing natural gas production levels. This has created new incentives to find materials that are active and selective towards alkane partial oxidation reactions that are relevant for natural gas...
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...
Raman spectroscopy is an analytical technique that utilizes inelastic scattering of light to obtain structural information of analyte molecules. The weak intrinsic process of Raman scattering, however, can be greatly enhanced when molecules are placed on or near a surface of noble metal with nanostructures. Discovered over 40 years, surface-enhanced...
Extensive study of nanomaterial chemical and optical properties has enabled their integration into a variety of applications. However, less thoroughly investigated are the heat generation and dissipation processes of nanomaterials following optical excitation. These phenomena are of immense importance as thermal energy can distort a material’s structure, which has profound...
Metal-organic frameworks (MOFs) are porous, crystalline materials synthesized by combining metal nodes and organic linkers through self-assembly. The diverse range of building blocks available allows for extensive tunability of MOFs, enabling the optimization of these materials for various applications, such as gas storage, separations, and catalysis. This study aimed to...
This thesis describes a novel demonstration of quantum teleportation, a protocol within the broader field of quantum information science, carried out by an electron transfer reaction within a molecular system. As described in Chapter 1, quantum information science has potential impacts in computation, communication, and cryptography. This field relies on...
Theoretical investigation of photochemical processes in molecules is a nontrivial task. Ab initio calculations that completely describe such processes are often intractable to perform given today’s hardware. Thus, to gain insight into common areas of interest, such as in transition metal photochemistry and organic photovoltaics, less accurate but more feasible...
The demand for low cost, unconventional electronics requires new materials with unique characteristics that the traditionally used silicon-based technologies cannot provide. Metal oxide semiconductors, such has amorphous indium gallium zinc oxide (a-IGZO), have made impressive strides as alternatives to amorphous silicon for electronics applications. However, to achieve the full potential...
Metal–Organic Frameworks (MOFs) is a class of material comprising organic linkers and inorganic, metal-ion-containing nodes, with diverse functionalities and wide-range of applications. Because of their porous nature and functional nodes and linkers, they are competent candidates for gas storage, separation, catalysis, and so on. Most MOFs, however, are intrinsically insulating,...
Quantum dots (QDs) are promising photocatalysts due to their large extinction coefficient, large surface area-to-volume ratio, and stability upon irradiation. QDs have been studied in photocatalytic hydrogen production, CO2 reduction, and reduction of small organic molecules such as nitrobenzene. This dissertation describes the application of QDs in two photocatalytic cross-coupling...
Secondary organic aerosol (SOA) particles are a class of highly abundant atmospheric constituents that represent a substantial fraction of carbon within the climate system. A subset of naturally-occurring SOA particles are formed through atmospheric oxidation of biogenic volatile organic compounds (BVOCs), forming oxygenated products of lower volatility that can partition...
Mixed-dimensional heterojunctions between two-dimensional (2D) materials and organic semiconductors is a rapidly growing field. This is motivated by the promise of leveraging the extraordinary properties of 2D materials with the synthetic tunability and reconfigurability of organic electronics, allowing the realization of new physics or devices that are not possible in...
Understanding the characteristics of interfaces between materials and solvent media such as structure, chemistry, and charge remains crucial to determining the properties and performance of numerous systems and technologies. This thesis focuses specifically on characterizing the interactions of water at oxide interfaces. A large collection of questions remains unanswered about...
This thesis document is comprised of three research projects. The first investigates the active vibrational modes involved in twisted intramolecular charge transfer in a Julolidine-BODIPY dyad using two-dimensional electronic spectroscopy along with DFT calculations. We identified two types of vibrations, compression and torsional motion, as playing an important role in...
High-throughput methods enable rapid experimentation and/or screening of thousands of samples simultaneously. Mass-spectrometry based methods are of particular interest since they provide a label-free way to detect all species present in a given reaction mixture. To circumvent sample preparation and purification—which is typically a slow process—the Mrksich group developed a...
Soft functional materials are fundamentally interesting from a chemistry standpoint and have exciting applications in robotics, chemical and biomolecule sensing, and biomedical engineering. In addition, soft materials are also useful in lithography, particularly cantilever-free scanning probe lithography (CFSPL). Because of their low modulus, biocompatibility, stimuli responsiveness, malleability, and other characteristics,...
In the first two decades of the 21st century, metal organic frameworks (MOFs) have attracted much attention in both fundamental-research and-industrial application areas. Derived from a vast library of both inorganic metal nodes and organic linker bridges, MOFs are crystalline materials whose structures and chemical environments can both be tuned...
DNA is extremely versatile and powerful, both as a construct in biological applications and as a ligand in materials design due to the fact that its recognition properties can be programmed through sequence and length. Spherical nucleic acids (SNAs), nanoparticles surrounded by a dense shell of DNA or RNA, are...
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...
The Controlled, Site-Isolated Synthesis of Polyelemental Nanostructures in Polymer Nanoreactors Pengcheng Chen Polyelemental nanoparticles are an attractive class of materials due to their potential applications, which span the fields of catalysis, plasmonics, electronics, magnetics, targeted drug delivery, and bio-imaging. However, conventional synthetic methods for such structures are limited, especially when...
Despite prevention and treatment, substantial risk for cardiovascular disease(CVD) remains in the population and CVD has been the leading global cause-of-death in past years.While high-density lipoprotein (HDL) markers such as HDL cholesterol (HDL-C) and HDL efflux (a cholesterol-transport-function assay) are associated with decreased risk of CVD, the mechanism of this...
Organic semiconductors have shown great promise for optoelectronic applications, particularly solar photovoltaics. Critical to their success is the ability to understand and manipulate the relationship between molecular structure and bulk properties. Substantial progress on understanding structural influences on electronic properties has been made for the conjugated polymers and small molecules...
Wireless power strategies are critical to system level implementation of bio-integrated devices. To achieve mechanically robust, manufacturable systems, batteries are often integrated as an on-board power source to support sensing, wireless communication and signal conditioning. Unfortunately, most sources of battery power use hazardous and environmentally harmful materials, which frustrate incorporation...
Among the most valuable applications of organometallic chemistry is its implementation in the field of catalysis. Many industrial processes rely heavily on catalysis, employing organometallic complexes in the production of commodity chemicals, fine chemicals, materials, and even in the discovery and development of pharmaceuticals. Through decades of intense study, homogeneous...
Biological therapeutics have revolutionized the way we treat cancer due to their ability to target tumors discriminately, leaving healthy cells unaffected. However, our inability to tailor the structure of biologics may hamper their optimization for efficacy. This lack of programmability contributes to factors such as immunogenic responses, inability to penetrate...
The objective of molecular imaging is to noninvasively visualize biochemical events in a living system at the cellular level. Magnetic resonance imaging (MRI) is a promising modality for this goal due to its excellent resolution, unlimited depth penetration, and absence of harmful ionizing radiation. MRI techniques frequently use Gd(III)-based contrast...
This thesis describes fundamental photophysical studies of quantum dot (QD)-molecule complexes, aimed at discovering strategies for enhancing the efficiency of QD-photocatalyzed and QD-sensitized multi-electron catalytic reactions, for the purpose of solar fuels production. Photosensitization of molecular catalysts that are active for reactions such as the reduction of carbon dioxide or...
Many processes in nature and human-made settings rely on the unique properties of charged metal oxide:aqueous interfaces. Despite their ubiquity, these buried interfaces are challenging to study, since any analytical technique aiming to overcome the relatively small number density of interfacial versus bulk species must be highly sensitive and surface-selective....
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...
This dissertation focuses on the study of the superionic state in multicomponent systems, where the smaller component exhibits delocalization and mobility while still maintaining system compactness through component attractions. Superionic behavior is widely observed in various systems and plays a crucial role in ceramic superionic conductors, which offer high ion...
One of the greatest challenges in heterogeneous catalysis is the rational design and development of new catalytic systems, due to synthetic limitations in the design of solid catalysts and inhomogeneity of chemical sites at solid surfaces. This obfuscates understanding of catalyst behavior and slows improvements of processes. One approach to...
This dissertation describes investigations into the two primary mechanisms by which the optical bandgap of colloidal quantum dots (QDs) may be post-synthetically modified: (i) by the quantum-confined Stark effect and (ii) by exciton-delocalizing surface capping ligands. This work demonstrates that through the use of ligand-exchange strategies that enable either of...
Clean water supplies are required for industry and general life. However, water shortages dueto pollution and human activity are increasingly common, and new, more efficient, materials need
to be made to increase clean water supplies. To do this, fundamental information on the interaction
of water with ions at the atomic...
In an era of personalized medicine, the clinical community has become increasingly focused on understanding diseases at the cellular and molecular level. Magnetic resonance imaging (MRI) is a powerful imaging modality for acquiring anatomical and functional information. However, it has limited applications in field of molecular imaging due to low...
It is said across numerous disciplines, from biology to architecture to software engineering, that “form ever follows function.” This adage highlights the intimate relationship between structural characteristics and functional properties in many disparate fields of work. Here, we discuss how the catalytic activity and compressibility of metal–organic frameworks (MOFs) are...
The continuing increase in atmospheric CO2 to concentrations exceeding 400 ppm has attracted considerable attention from both scientists and policymakers. Industrial fossil fuel consumption generates a significant amount of CO2 emissions, and in particular, energy-intensive molecular separations that require thermal processes, such as distillation, drying, or evaporation, are responsible for...
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...
Deciphering the targets of axonal projections plays a pivotal role in interpreting neuronal function and pathology. Neuronal tracers are indispensable neurobiology tools for elucidating advanced functions and interactions between different subregions of the brain. Commercially available neuronal tracers include small molecule dyes, viruses, and synthetic nanoparticles. Among these options, viral...
This work combines the use of high-throughput mass spectrometry with peptide arrays for to monitor reactions on peptides. The Mrksich lab introduced a high-throughput, label-free, biochemical assay that relies on self-assembled monolayers on gold and matrix-assisted laser desorption/ionization mass spectrometry, termed SAMDI-MS. This dissertation introduces new applications of SAMDI-MS and...
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...
Carbon nanomaterials, such as graphene and graphene oxide, have outstanding mechanical strength, stiffness, and toughness that surpass those of materials currently used to build structures. However, these properties are limited to the nanoscale and have not yet been attained in macroscopic composites containing carbon nanomaterials. To integrate the mechanical properties...
Total synthesis of natural products provides an avenue for investigation of complex chemical scaffolds, not only delivering access to biologically impactful molecules but also lending a deeper understanding of their inherent chemical reactivity. Expansion of reaction methodology, optimization of biological activity, and absolute structural confirmation can all be accomplished via...
Two-dimensional (2D) hybrid halide perovskites have been the response to their exciting but woefully unstable 3D counterparts. These 2D perovskites have been shown to have respectable stabilities as photovoltaic absorbers, yet they lag behind the 3D perovskites in terms of efficiency. With the need to catch up to the efficiencies...
The mammalian oocyte undergoes large fluctuations in zinc content as it matures from a prophase I arrested oocyte to a metaphase II egg and finally is fertilized to become a zygote. These changes in total zinc content are necessary for proper progression, as disruption to egg’s ability to acquire and...
Thermoelectric modules that convert heat into electrical energy are attractive for improving global energy management. This thesis reports the synthesis and characterization of two new families of lead and tin chalcogenide alloys and focuses on the impact of the grain boundaries, phase segregation, and atomic vacancies on the electronic and...
Dynamic covalent chemistry (DCC) combines the strength and directionality of covalent bonds with the reversibility of supramolecular interactions. The formation and stability of these bonds are typically regulated by parameters such as temperature, pH, concentration, catalyst loading and light. Light is an exceptionally powerful stimulus because it can be applied...
The ubiquitous role of water in biochemical, electrochemical, and geochemical systems has driven scientific interest in studying the fundamental hydrogen-bonding interactions that water molecules exhibit in the presence of different materials.Specifically, we focus on the interactions characterizing water at the interface between two bulk media, as these are essential to...
Organic chromophores show great promise for energy and optoelectronic devices, due to their synthetic tunability and low production costs. In order to achieve this potential, their fundamental photophysical processes must be better understood. It has long been documented that chromophore packing at the molecular level has dramatic effect on electronic...
Chirality and polarity describe orthogonal mechanisms of inversion symmetry breaking, which is the origin of valuable properties in crystalline materials including nonlinear optical activity, ferroelectricity, and piezoelectricity. Noncentrosymmetric (NCS) materials have numerous applications yet opportunities remain for cooperative coupling between chiral and polar basic building units to realize high-performance materials....