The Hill Lab at UW
We’re a group of electrochemists in the Department of Chemistry at the University of Wyoming. As electrochemists, we’re interested in the behavior of heterogeneous interfaces which play critical roles in energy conversion, catalysis, and sensing. Our laboratory develops and applies new microscopy tools to visualize chemical and physical processes occurring within these complex systems, generating new fundamental insights to help guide the design of improved practical devices. We are particularly interested in tools which can interact with “single entities” present at these interfaces, such as nanoparticles, defects, or even individual molecules/atoms!
Our lab’s mission is simple: to help train the next generation of electrochemists and do some cool science along the way. Students and postdocs working with the lab receive training in a variety of areas, including electrochemistry, materials synthesis, instrumentation development, numerical simulations, optics, and spectroscopy, as well as the “soft” skills needed to succeed in a professional scientific setting. We are committed to creating a welcoming, supportive environment where all members feel empowered to reach their full potential.(that’s a bad electrochemistry joke)
Ongoing Research Projects
Single-Entity Catalysis: Electrocatalytic reactions play a central role in technologies for energy conversion (water splitting, fuel cells) and negative emissions (CO2 conversion). To run efficiently, these reactions must occur at the surface of appropriate catalysts which stabilize key reaction intermediates. Designing efficient, stable, yet cheap catalyst materials will be central to the continued development of these technologies. Our lab is developing and applying single-entity electrochemical methods to characterize electrocatalytic reactions occurring at individual nanoparticles. These systems are often quite complex, exhibiting particle-to-particle variations in size, shape, and/or composition which make understanding these materials difficult. We are applying a technique developed in our laboratory, Targeted ElectroChemical Cell Microscopy (TECCM), to carry out high-throughput, single-entity studies of a variety of catalyst systems. This approach will allow us to rigorously explore the complex parameter spaces of these materials in a manner not previously possible, identifying ideal structures or compositions to employ in practical devices.
Visualizing Carrier Transport in 2D Semiconductors: 2D semiconductors (2DSCs) are semiconductors which exhibit strong, covalent bonding in only 2 dimensions. While many of these materials have been known for several decades, their fabrication as sub-nm monolayers has only recently been explored. Interest is utilizing these ultrathin layers as active components in devices for solar energy conversion, photodetection, etc. has since exploded due to the unique physical properties many 2DSCs exhibit at this scale. Before such applications can be realized, however, we need a better understanding of how different structural motifs present in realistic crystals (e.g., step-edge defects) influence their operation. Our group is designing experimental schemes to directly visualize how photogenerated carriers are transported within these materials, and particularly how local structural variations affect these processes. We do this using variants of Scanning ElectroChemical Cell Microscopy, in which small electrolyte-filled pipets are brought in contact with an array of small spots across a sample, allowing us to directly image how photoinitiated reactions vary across a sample with high resolution.
Better Sensing through Ordered Nanoparticle Arrays: Nanoparticles can be employed as key elements in a variety of optical and/or electrochemical sensing technologies. However, it is fundamentally challenging to control the spatial arrangement of such nanoscale entities on surfaces, which is necessary to achieve the desired sensor performance and a high degree of reproducibility in fabrication. In our lab, we’ve been exploring how electrochemical microscopy techniques can be reimagined as flexible, on-demand tools for the fabrication of ordered nanostructure arrays and utilize these tools to construct better performing sensors for a variety of analytes.
Funding
We are grateful for the generous support our work has received from the National Science Foundation (CHE-2045593, OIA-2119237, CHE-1762161), the Department of Energy (DE-SC0021868, DE-SC0018561), Idaho National Laboratory, the Wyoming NASA Space Grant Consortium, Wyoming INBRE, and the University of Wyoming.