Student Research: VIPER Class of '19

Avery Bang:  Avery spent her summer working on an independent project under Dr. John Bassani's supervision in collaboration with Holtec International, a leading nuclear waste company, in developing a model to predict long-term cladding behavior of nuclear spent fuels in storage and transportation. Spent fuel rods from nuclear reactors should be stored for at least 300-years in order to ensure safety from nuclear reactions, and due to its long storage spent fuel has been building up around the world along with the need to evaluate their property in the future. While models for short-term behavior exists, Avery hopes to extend these preexisting models to better evaluate spent fuel's safety in their entire lifespan.

Siddharth Challani:  Over the summer, Siddharth worked in Dr. Mark Allen’s lab under the guidance of Dr. Minsoo Kim, exploring different processes that are important for work in the MEMS (micro-electromechanical sensors) field. He was exposed to projects in electromagnetics and microfluidics before settling into a project on self-assembled monolayers and their ability to decrease the massive amounts of time and money necessary in microfabrication processes.

Hyuck Choi:  Hyuck spent his first summer in the lab of Prof. John Vohs in the Department of Chemical and Biomolecular Engineering, investigating the correlation between the geometry of the TiO2 nanocrystals in TiO2 catalysts and their catalytic activity. Through the results obtained from Temperature Programmed Desorption (TPD) runs and the microbalance, Hyuck compared how the sets of product yield obtained from different sized TiO2 nanocrystal rods varied. Through the results of this project, Hyuck wishes to gain a better understanding in how to characterize catalysts, which play an important role in many energy storage devices such as Solid Oxide Fuel Cells (SOFC), which will maximize their efficiency.

Emily Cunningham: Emily’s research was conducted in Professor Raymond Gorte’s lab in the Department of Chemical and Biomolecular Engineering. Certain metal oxides show great potential for use in water-gas shift catalysis in fuel processors. The goal of these experiments was to improve the thermal stability of common supported catalysts by coating the surface of the catalyst with a uniform metal oxide layer via Atomic Layer Deposition. The mass of the samples was tested after every five rounds of Atomic Layer Deposition to ensure that the nanoparticle layers were uniform. In this specific project, iron was deposited onto alumina supports and calcined at several different temperatures before being tested in methane oxidation chambers. The reaction rate testing showed that the metal oxide layers did in fact increase the catalytic activity of the alumina support.

Kyle Kersey:  This past summer, Kyle worked under Dr. Eric Schelter in the Chemistry department developing synthetic uranium coordination compounds for the synthesis of a new moiety in uranium chemistry, a U=C bonded compound. In performing this work, Kyle characterized a new ligand through NMR and IR spectroscopy and mass spectrometry for complexation to uranium. The goal of this research was to create a series of stable complexes as precursors for the target compound. One hypothesis for this work was that complexes with axial symmetry will facilitate access to such a bond due to the inverse trans influence, a strengthening of axial bonds unique to actinides. This research furthers fundamental understanding of high oxidation state actinide chemistry and has potential applications in more secure and predictable storage methods for spent nuclear waste.

Yann Pfitzer:  Yann worked in Dr. Irina Marinov’s lab in the department of Earth and Environmental Science, investigating the ramifications of climate change on biological microorganisms and processes that take place in the ocean. The main focus of the research was to study how the changing environment impacted the growth of Phytoplankton, this organism is of particular interest since it accounts for approximately 50% of the photosynthesis on the planet and is thus the largest carbon sink. The warming and cooling of the ocean have a large impact on the phytoplankton’s access to nutrients and light since temperature is the determining factor in the ocean’s stratification. A part of Yann’s work was to study the trend in the ocean’s stratification. An increasing stratification would theoretically lead to a decrease in phytoplankton because their access to nutrients would be hindered. On the other hand, a decrease in stratification could result in more favorable conditions for phytoplankton since more nutrients would upwell from the bottom. The preliminary results were obtained by doing statistical analysis of measured data from 1997 to 2014 and showed that in some regions, as temperature increased, the stratification decreased.

Justin Qian:  This summer, Justin worked in Dr. Ritesh Agarwal's lab along with graduate student Zhurun Ji on optimizing the chemical vapor deposition growth of monolayer MoS2 crystals. MoS2 is a transition metal dichalcogenide with interesting optical and electrical properties. We were able to grow 6 point stars domains of MoS2 flakes on the upstream end of our SiO2 substrate by using the precursors MoO3 and S2. We heated our precursors under different temperature programming with an Argon flowrate of 10 s.c.c.m in a quartz tube. Further work will be focused on improving the reliability and domain size of our current growth method. Additionally we would like to observe the shape evolution of the MoS2 flakes when using different parameters.

Nathan Xu:  Nathan spent his summer conducting research on new forms of nanotechnology in Prof. Mark Allen’s microelectromechanical systems (MEMS) lab. He worked on a new approach to develop nanotechnology is using microelectromechanical systems (MEMS) methods. Using MEMS methods, he created patterned micro-nanostructure channels of specially treated PDMS, which significantly improved flow velocity. Further, a reusable master mold template that could precisely reproduce metallic microstructure layers at thin thickness was created using patterned photoresist and a copper seed layer that was coated with dodecanethiol. In the lab, roughly 1.5 micron thick sheets of copper were created with easy reproducibility using this new method.