(3du) First-Principles Modeling of Electrochemical Interfaces

A societal shift towards greater adoption of renewable energy is underway. According to the International Energy Agency, the share of global energy consumption produced from renewable sources is projected to increase by 20% over the five year period from 2018 to 2023. To accelerate this transition, new approaches for energy production, conversion, and storage are needed. Among the most promising technologies to address these areas are electrochemical systems (e.g., fuel cells and batteries). However, the fundamental properties that govern the interfaces in these systems currently limit the utility of these technologies. My work investigates these limitations by applying first-principles, electronic and structural analyses to the design and understanding of interfaces in electrochemical systems.

I am interested in translating atomistic features to macroscopic performance in electrochemical systems. In my work, I have meshed approaches common in the study of interfaces in electrocatalysis with those in batteries to develop a unique area of exploration. This includes employing density functional theory (DFT) simulations to relate the electronic structure of active sites in electrocatalysis to bulk catalytic activities, using molecular dynamics simulations to examine the transport of metal cations at material interfaces, and applying data-driven approaches to deduce material property descriptors predictive of performance metrics.

I am particularly interested in examining materials that are not stable in the bulk, but are stabilized as thin surface films. These types of materials are underexplored in the literature, but are often able to explain complex phenomena in electrochemical systems. Using electrochemical potential as a knob to tune the stability of these structures, it is possible to tailor reactivity and transport properties for desired applications. Although I am a computational scientist, in my research, I work closely with experimentalists to integrate computation and experiment. My focus is not simply to validate a set of experiments, but to combine computation and experiment throughout the course of a study.

Research Experience

During my PhD, I worked with Professor Don Siegel at the University of Michigan to employ first-principles modeling to the study of anode/electrolyte interfaces in next generation battery chemistries. In my work, I used DFT calculations to determine the thermodynamic driving force and kinetics of plausible decomposition reactions on Mg anode surface compositions. My calculations predicted the rapid decomposition of a common solvent molecule to ethylene gas on the metallic Mg surface, a result which was recently observed by others through both experimental and further computational techniques. I further showed that the presence of an oxide or chloride surface film may limit this unwanted decomposition pathway. I also investigated the interface formed between lithium metal and its native oxide for applications in lithium metal batteries [1]. I created a realistic model of the Li/Li₂O interface through the stepwise addition of O₂ molecules to an initially pure Li metal surface. The resulting interface, which was predicted to be the most probable under equilibrium conditions, was shown to provide facile transport of Li ions. This result can be exploited to improve the transport of Li⁺ at the anode/electrolyte interface.

In my role as a Lillian Gilbreth Postdoctoral Fellow in the Departments of Chemical Engineering and Chemistry at Purdue University, I work with Professors Jeff Greeley and Christina Li to bridge their expertise in computational and experimental techniques in electrocatalytic systems. In one project, I focused on understanding the role of metal nanoparticles in tuning the electronic properties of metal chalcogenide ligands for improved catalytic behavior in the hydrogen evolution reaction (HER) [2]. Using DFT, I was able to show how the metal support (Au) modified the atomic and electronic structure of the MoS₄^2- ligands, and the findings were consistent with our experimental results. I then used a computational descriptor to relate the electronic modification to HER performance. Overall, both computation and experiment showed improved HER activity with the electronic modification. In another project, I am investigating the performance of indium (hydroxy)oxide films on platinum nanoparticles for CO electrooxidation [3]. My work in this area is ongoing, but I have shown that the stability range of indium (hydroxy)oxide phases is modified when these phases are present as a monolayer on Pt(111) as compared to the range of stabilities predicted from bulk energetics alone. These findings may suggest the improved performance evidenced by this indium catalyst in our recent experimental research.

Teaching Interests

I am very passionate about teaching and have dedicated a considerable amount of my time over the last several years to mentoring students and teaching development. I have mentored numerous students in the research lab, and have also served as a mentor through more formal programs, assisting graduate students at the University of Michigan in their first year of the PhD program and working with Master’s students at Purdue University to make the transition to PhD programs. During my PhD, I trained new graduate student instructors, facilitated workshops that focused on problem solving, writing, and practice teaching, completed courses and workshops on teaching, and served as a graduate student instructor (for roughly 300 students) in two engineering courses (Thermodynamics and Reaction Engineering). I experienced the benefits of applying research-based principles to teaching and discovered that by diversifying my approach to include learners of all backgrounds and learning styles, I could be more effective as an instructor. As a faculty member in chemical engineering, I would welcome the opportunity to teach core departmental courses (such as Thermodynamics and Reaction Engineering), or elective courses in line with my research (e.g., Renewable Energy Systems, Scientific Computing, etc.).

AIChE Conference Presentations (this year)

[1] J.S. Lowe and D.J. Siegel, “Probing the lithium metal anode surface with first principles”

[2] J.S. Lowe, V. Yadav, A.J. Shumski, E. Liu, J. Greeley, and C.W. Li, “Structural and electronic analysis of chalcogenide-functionalized gold nanoparticles from first principles”

[3] J.S. Lowe, C.W. Li, and J. Greeley, “Indium (hydroxy)oxide films on platinum nanoparticles for CO electrooxidation”