Daphne Garcia
The focus of my research is to develop new electrode materials for energy storage devices by improving current chemical processes of dealloying brass sheets to create three-dimensional nanoporous copper structures. By controlling the dealloying process, a more even distribution of pores that are all less than a micron in diameter and greater surface area in the structure will be achieved. These structures will function as current collectors in lithium-ion batteries, with the potential for higher energy density, increased cyclic performance and rate kinetics. Variables such as dealloying chemical composition, brass composition, and sheet thickness will be analyzed to identify the ideal conditions for achieving...
Diwash Dhakal
Rechargeable batteries are among the candidates that can fulfill the evolving energy storage needs and are being researched extensively. My research focuses on the application of X-ray spectroscopy techniques to better understand the critical processes in rechargeable Zn-ion batteries (ZIBs). Specifically, I am looking at the local chemical environment and coordination complex in electrolytes and ion pairing in the electric double layer at electrode interfaces. Such a study will lead to a better understanding of the role of ion pairing on both structure and dynamics at the electrode-electrolyte-interface, a key question for ZIBs and many other battery systems. Advisors: Gerald T. Seidler, Guozhong Cao -...
John Cenker
Two-dimensional van der Waals crystals hold great promise for future devices due to their atomically thin nature and the consequent unique emergent physics. Furthermore, their pristine crystal lattices should make them extraordinarily robust to external stresses such as strain. My research focuses on developing new ways to apply strain to 2D materials to drive phase transitions which can be harnessed for future device applications. For example, applying strain to atomically thin magnets to drive magnetic phase transitions. This research could enable energy-efficient, ultrathin memory bits which can be written purely by an applied voltage to the strain cell. Advisor: Xiaodong Xu - Physics...
Christian Pederson
Simulating novel materials with the desired range of properties for efficient solar energy collection, or storage is computationally intractable with classical computers. Quantum computers and simulators are the only known devices that can efficiently tackle these problems, yet are plagued by the experimental challenges of scaling up sensitive quantum systems. I will investigate an integrated photonics platform based on point defects in diamond. Significant challenges remain, but integrated devices have a clear path to scalability since they build upon existing semiconductor fabrication methods. Recent work demonstrated that a particular defect, the silicon-vacancy(SiV) center, could be created nanometers from the surface of diamond without compromising its...
Jiaying Yang
Electrocatalytic conversion of CO2 into useful chemical resources is a compelling strategy to mitigate the effects of climate change, but accomplishing this goal requires the development of next-generation catalysts. Highly selective homogeneous catalysts suffer from low stability, while robust heterogeneous catalyst cannot be easily tuned for selectivity. Immobilization of molecular catalysts on heterogeneous supports provides more robust catalytic systems with high selectivity and activity. Through my research, I will investigate the surface functionalization of phosphorene, a two-dimensional phosphorous analogue of graphene with a thickness dependent bandgap. The support was chosen because it can be viewed as a solid-state phosphine ligand poised to coordinate to transition metal...
Parker Steichen
My research focuses on the application of sulfide solid electrolytes in all solid state batteries (ASSB). While the high ionic conductivity of these materials have sparked significant interest amongst researchers, poor electrochemical stability has been a significant obstacle to realizing practical sulfide electrolyte based ASSBs. I am looking at how we can improve the long term stability of these materials so that we can realize practical and robust high energy density ASSBs. Advisor: Jihui Yang - Materials Science & Engineering...
Kevin Lee
Nanostructured alloying electrode materials such as antimony, germanium, and silicon are highly promising materials that offer potentially low-cost, high-power-density, and high rate capability. However, developing a strong understanding of the morphology and tying the morphology to performance is difficult because electrodes are typically made up of a disordered mixture of active material, polymeric binder, and conductive carbon. Therefore, the goal of my research is to utilize in-situ electrochemical techniques such as the galvanostatic intermittent titration technique (GITT) and electrochemical impedance spectroscopy (EIS) to fully understand how alloying type nanomaterials behave in multicomponent electrochemical systems such as batteries. The investigated materials will be synthesized using...
Lixin Lu
Doped metal-halide perovskites CsPbX3 (X=Cl, Br or I) nanocrystals (NCs), which combine the desirable broadband absorptive properties of perovskite semiconductors with the richly tunable color emission profiles of sensitized metal ion dopants, have a great potential in the application of high-efficiency solar cells, LEDs, and lasers. Successful doping of various trivalent lanthanide ions (or rare earth ions, RE) into colloidal perovskite NCs has been recently reported. For example, ytterbium (Yb3+)-doped CsPbX3 exhibits over 100% photoluminescence quantum yields (PLQY) as a result of picosecond quantum cutting process, indicating its opportunities to serve as downconverters in solar-energy-conversion technologies. Despite of the experimental evidence, the electronic structural...
Leo Zasada
My research focuses on new, advanced materials for efficient energy storage and electrocatalysis. Specifically, I will synthesize liquid crystalline metal–organic macrocycles that combine the porosity, chemical tunability, and high conductivity of 2D metal–organic frameworks (MOFs) with the solution-processability, self-healing, and stimuli-responsiveness of liquid crystals. 2D MOFs are generally isolated as microcrystalline powders, leading to poor electron transport across grain boundaries. In contrast, liquid crystals are solution processable and can be macroscopically aligned, eliminating this issue. I have synthesized tetrahydroxytriphenylene ligands that should bind to square planar M(II) cations to form hexagonal macrocycles. The desired macrocycle features a π–d conjugated core that should facilitate rapid charge...
Jiaqi Cai
One of the CEI missions is to develop next generation’s energy saving technologies. To date, the information processing is accompanied by inevitable energy dissipation in devices caused by impurity scattering. Very recently, a new phase of matter, named as magnetic topological insulator (MTI), emerged as a promising platform to develop dissipationless electronics, where carriers transmit along the edge of the devices without any energy loss. This dissipationless property is ensured by the topological nature which enables the edge conduction to be immune from bulk impurity scattering. What’s more, the interplay of magnetism and non-trivial topology in MTI makes the electronic state controllable, enabling the devices to...
David Rosser
Materials science forms the foundation for advancement in modern technologies. The advent of quantum simulation to supplant the need for trial and error of experimental material discovery or large-scale supercomputer simulations for seemingly simple molecules is altogether appealing. However, the near-term prospects of useful noisy intermediate-scale quantum technologies is limited. An alternative paradigm, termed quantum emulation, proposes to map difficult problems to simplified lattice models which describe the relevant physics. My research focuses on the integration of monolayer van der Waals materials onto patterned, foundry-compatible dielectric materials for study of the interaction between optical transitions, provided by the van der Waals materials, and the...
Mareldi Ahumada Paras
My research is focused on resiliency of power systems, specifically in recovery optimization after outages caused by extreme events such as hurricanes, earthquakes and storms. 1) Use data driven case study to optimize utility schedules of repair crews and enhance the recovery phase of a power outage. 2) Quantify the impact of natural gas faults on power generating units in a co-optimized framework. Advisor: Daniel Kirschen - Electrical & Computer Engineering ...