Gillian Shen
My research involves the design, fabrication, and optimization of quantum dot light-emitting diodes (QLEDs) for next-generation lighting and displays. As lighting accounts for 15% of global electricity consumption, advances in the energy efficiencies of lighting technologies would be a significant step towards reducing our global energy footprint. Mechanistic understandings of the excited state dynamics in quantum dots for QLEDs will also enable simultaneous advancements in quantum dot photovoltaic devices for more efficient solar cells. The first aspect of my work involves the synthesis of perovskite quantum dots with carefully controlled synthetic parameters and post-synthetic treatments for the growth of monodisperse, defect passivated, and highly...
Sage Scheiwiller
Blends of conjugated and commodity polymers provide a way to balance desirable electronic properties and physical properties of both components. This balance plays a critical role in the development and performance of organic electronic devices such as photovoltaics (OPVs), field-effect transistors (OFETs), bioelectronics, and wearable sensors. Understanding the fundamental interactions between the conjugated polymers and matrix polymers at all stages of processing is essential for designing and optimizing organic electronic devices. My research focuses on understanding the structure property relationship in solid and solution states in order to track how the pressures of processing and composition change the morphology and the film properties. Advisor: Lilo...
Michael Riehs
My research involves using concepts and techniques from molecular inorganic chemistry to alter the properties of two-dimensional materials for use in catalysis. Specifically, I am working on functionalizing semiconducting black phosphorus with transition metals that can serve as active sites for reactions such as hydroformylation. Synthesis of this type of material from the bulk down to a single atomic layer can provide insight into metal support interactions that often dictate how a catalyst behaves. Advisor: Alexandra Velian – Chemistry...
Meredith Pomfret
Rigid rod polymers are a class of high-performance materials made up of a conjugated, heteroaromatic backbone that have applications spanning engineering and electronics. Unfortunately, due to their chain stiffness, thermal recycling and solution-state processing of these materials can be very difficult. My research is focused on incorporating the ‘shape shifting’ small molecule bullvalene into rigid rod polymer chains to modulate the polymer physical properties while maintaining the desired thermal and chemical stability. Bullvalene undergoes rapid Cope rearrangements at room temperature to access 1.2 million degenerate isomers. Within a polymer chain, bullvalene leads to a dense, coiled chain conformation due to an ensemble of different...
Heonjoon Park
Two-dimensional semiconductor moiré superlattices are a powerful platform for engineering correlated electronic phenomena. My research focuses on the exploration of the extended Bose-Hubbard model of exciton lattices in twisted transition metal dichalcogenide moiré materials. I employ optical techniques to probe emergent phases in interacting opto-moiré quantum matter. Advisor: Xiaodong Xu - Physics...
Emily Nishiwaki
Alcohols are energy-dense fuels and small-chemical building blocks for electrosyntheses of commodity chemicals and fuels. Developing earth-abundant alternatives, such as nickel, to noble metals as catalysts for alcohol electro-oxidation is a critical step towards global sustainability. Nickel-based materials catalyze this reaction by forming a layer of NiOOH (in alkaline conditions) that assists in the rate-limiting deprotonation step of the alcohol on a surface. My research involves synthesizing a series of Ni-based nanocrystals (Ni2P, Ni3S2, Ni3B, etc) and exploring how the incorporation of additional non-metals modulates surface energetics. Additionally, I will be investigating how the oxy-hydroxide layer forms on different nanocrystals and ultimately impacts activity...
Hao Nguyen
My research currently has two focus areas. The first is the development and deterministic positioning of giant core/shell quantum dots for integration into photonic nanobeam cavities to achieve strong light-matter coupling for quantum applications. My second project involved the use of machine learning as a tool in nanomaterial synthesis. Understanding hidden mechanisms of nanomaterial synthesis will help design new environmentally friendly synthetic routes and realize 'green' precursors for these processes. Advisor: Brandi Cossairt - Chemistry...
Ben Mitchell
Heterogenous catalysis is of fundamental importance to the chemical and energy industries and developing next generation catalytic systems will be essential for the transition to a sustainable future. However, comprehensive understanding of the physical processes occurring at catalytic interfaces, an essential criterion for innovation, is a challenge due to difficulties in obtaining atom level insights from modern surface spectroscopies. My research has focused on the development of atomically precise molecular nanoclusters which feature well-defined, substrate-accessible active sites in contact with a [CoSe] inorganic cluster, effectively mimicking a catalytic interface. Using strategies available to molecular chemists I can probe the dynamic substrate/active site/support interactions and...
Xuetao Ma
Bulk materials at the 2D limit can host untrivial electronic properties. My research works on exfoliating bulk topological materials, building those materials into nanodevices, and studying their transport properties under extreme conditions such as low temperature, high pressure, and strain. I have developed techniques that can apply pressure or strain to 2D nanodevices that are compatible with low-temperature measurements. Those techniques provide new tuning knobs to transport measurements so we can tune the strength of existing untrivial states and discover new states. Advisors: Jiun-Haw Chu, Matthew Yankowitz...
Xiaolin Liu
To efficiently utilize solar power, the energies absorbed by molecules must be channeled somewhere else for energy storage or catalysis. Bimetallic complexes where some conjugate ligand connects the two metal centers are the simplest models for multi-metallic complexes occurring in natural photosynthesis systems. I study the charge and energy transfer processes in these systems using real-time and Ehrenfest dynamics methods to facilitate the better design of solar cells and photocatalysts. The other project of mine involves developing a highly accurate relativistic wavefunction method (exact two-component equation-of-motion coupled-cluster) to study K- and L-edge spectroscopy of small molecules. Advisor: Xiaosong Li - Chemistry...
Ben Link
My research is centered on leveraging computational chemistry for rational design and specific description of electronic and nuclear excitations. Specifically, my research centers on using the nuclear-electronic orbital (NEO) method to treat select nuclei, usually hydrogen, on the same footing as electrons. This allows us to study quantum nuclear effects and their role in processes necessary for many energy processes both in nature and in alternative energy sources, including proton-coupled electron transfer (PCET) and excited-state intramolecular proton transfer (ESIPT) events. Understanding these processes allows for theoretical studies of dye-sensitized solar cells, and can allow for predicting higher efficiency and lower cost of photoelectric upconversion. Advisor:...