(2al) Transport-Directed Electrosynthesis for Decarbonization of Chemical Manufacturing

Electrochemical engineering will be critical to the development of future technologies used to decarbonize the chemical industry. Historically, chemical engineers have undertaken the development and scaling-up of chemical processes to meet industrial demand without adequate consideration for the environment. However, the damaging impacts of global climate change have necessitated a paradigm shift—modern chemical engineers must develop sustainable alternatives that surpass conventional energy efficiencies and are commercially scalable. Crucially, the systems that will enable such transformations leverage renewable electricity as a driving force and differ significantly from traditional, thermally-driven chemical processes. These systems operate far from ideality and possess complex, multiphase interfaces, where highly concentrated species exist out-of-equilibrium, under the influence of electric fields, and in mass-transport-controlled regimes. Consequently, conventional chemical engineering frameworks must be augmented with a fundamental, multiscale understanding of the complex interplay between transport and reaction kinetics. I am interested in developing the continuum theory and computational methods necessary to describe electrochemical reactors across multiple length and time scales. My group will also exploit our physical understanding to design and fabricate reactors wherein deliberate tailoring of transport is employed to unlock unprecedented activity, selectivity, and durability for reactions critical to decarbonization of the chemical industry.

Research Experience:

As a faculty member, I plan to build upon the computational methods developed during my doctoral studies at U.C. Berkeley and Lawrence Berkeley National Laboratory working together with Dr. Adam Weber and Prof. Alexis Bell. During my Ph. D., I developed continuum approaches to resolve the impact of ion transport and chemical microenvironment on the performance of electrochemical reactors for carbon removal and conversion. The key achievements of my research include:

1. I developed a modified Poisson-Nernst Planck framework that fully captures the coupled transport of ions and solvent in bipolar membranes (BPMs), accounting for non-equilibrium behavior and electric-field enhanced speciation kinetics. The model reproduces experimental behavior for BPMs exchanged with varying compositions of electrolyte, elucidating physical phenomena in BPMs relevant to electrocatalysis, carbon capture, and flow batteries.
2. I integrated data science tools and continuum modeling to uncover how mass transport influences apparent catalytic behavior in electrochemical CO₂ This work showed that mass transport commonly convolutes kinetic data collected during electroanalytical experiments due to the limited solubility of CO₂ as well as the presence of out-of-equilibrium buffer reactions that further consume CO₂ and modulate local pH near the catalyst surface. The associated code is openly accessible to the scientific community.
3. I conducted continuum simulations of electrochemical CO₂ reduction in planar flow reactors and membrane electrode assemblies (MEA) to examine the impact of species and solvent transport on efficiency, activity, and selectivity. These simulations reveal transient activity enhancements accessible by pulsed operation, the crucial role of water management in high current density operation, and the importance of managing intermediate transport in cascade catalysis schemes.

Leveraging continuum theory to describe microscale environments within electrolytes and at interfaces, my work has employed an understanding of transport to guide the design of electrochemical devices for carbon capture and conversion. Importantly, the governing physics employed are universal, so the insights discovered are translatable to other electrosynthesis chemistries (e.g., nitrate reduction, electro-organic synthesis) or environmental applications (e.g., wastewater treatment, desalination). My doctoral work has established the crucial role that transport plays in dictating the performance of electrochemical reactors applied in energy or environmental applications.

Future Research

The Bui Group will couple continuum models informed by a fundamental understanding of transport and catalysis with high-throughput experimentation to accelerate the development of electrochemical technologies key to decarbonization of the chemical industry. Our chemistries of interest will be the manufacture of (i.) cement clinkers with BPM reactors, (ii.) nitric acid via nitrogen oxidation, and (iii.) ethylene oxide via electrochemical oxygen atom transfers to ethylene. We will advance theory describing non-ideal phenomena such as coupled species transport beyond the dilute regime, electric-field-enhanced catalysis, and mixed-solvent effects, within the context of continuum models of the electrode-electrolyte interface. Leveraging data science tools, these models will be coupled with high-throughput experimentation where the unique transport characteristics of microfluidics will be exploited to rapidly screen the impacts of electrolyte composition, operating potential, temperature, and pressure on electrocatalysis. We will employ additive manufacturing to fabricate microfluidics tailored to this application, with integrated reference electrodes, well-defined transport, and operando characterization of the inlet and outlet streams. This combination of modeling and experimentation will uncover transport and reaction mechanisms that will guide design in the scale-up to industrially relevant MEA-stack reactors. At larger scales, physics-based modeling and basic-science approaches will resolve degradation mechanisms and enhance durability, expediting industrial deployment. These methodologies will establish design principles for electrochemical systems vital to decarbonization of the chemical industry.

Teaching Interests:

My foremost long-term impact as a faculty member will be mentorship of students in the laboratory and the classroom. To date, I have consistently pursued opportunities to engage with and enhance my teaching abilities. As an undergraduate at Columbia, I served as a teaching assistant for five semesters, teaching computer-assisted design, material and energy balances, undergraduate-level thermodynamics, and graduate-level computational fluid dynamics. At U.C. Berkeley, I have maintained this commitment as a graduate student instructor for both undergraduate-level and graduate-level transport phenomena, receiving the Outstanding Graduate Student Instructor Award for teaching the graduate-level course. Furthermore, I have mentored seven undergraduate research students, who have worked on various problems related to electrochemistry, and have collectively published five peer-reviewed manuscripts. Throughout this time, I have sought to foster personal connections with my students, helping them discover their interests and establish a professional network to help advance their career goals. Many of these students are now pursuing doctoral degrees or working in industry. One of my mentees, Alexandra Ramos, is pursuing a Ph. D. at Stanford on the NSF GRFP, the GEM Fellowship, and the Stanford Graduate Fellowship. Another mentee, Kaitlin Corpus, will attend Columbia for her Ph. D. and received the John Prausnitz Award for having the best research in her graduating cohort at U.C. Berkeley. Outside of traditional roles, I have developed an experiential, active-learning curriculum to teach elementary-school students the basics of solar water splitting. Partnering with Community Resources for Science, I directed an educational study to assess the curriculum's efficacy, published in the Journal of Chemical Education, that demonstrated that the active-learning pedagogy improved student outcomes and reduced performance gaps between under- and over-represented student populations. As a faculty member, I hope to maintain connections with the education community to develop further curricula that advances scientific outreach, as well as to forge connections with my local community to bring these lessons to new students.

My background in chemical engineering, has prepared me to teach all core courses in the undergraduate or graduate curriculum. While I hope to teach a broad array of courses throughout my career, my greatest enthusiasm lies in teaching transport phenomena or thermodynamics. In addition to these courses, I hope to develop (i) an undergraduate-level course on the basics of electrochemical engineering, and (ii) a graduate-level course on advanced transport in electrochemical systems. I am also eager to create new curricula that incorporate electrochemistry into existing core courses. Ultimately, I plan to convince students that the fundamental principles of chemical engineering are versatile and applicable to a wide range of challenges. Hence, I hope students emerge from my courses possessing not only subject-level mastery, but also transferrable skills in creative problem-solving and an improved comprehension of their evolving roles as chemical engineers in the modern world. My teaching style emphasizes active learning, and I am committed to promoting a diverse, inclusive culture within my classrooms wherein differences in student learning styles are accommodated, and students can face complex concepts without fear of failure. I will strive to use my position as a professor to enhance diversity and retention of underrepresented minorities within my university and the scientific community.

Selected Awards

National Defense Science and Engineering Graduate (NDSEG) Fellowship (2021)

NSF Graduate Research Fellowship (2019)

AIChE Excellence in Graduate Polymer Research Award (3^rd Place) (2022)

ACS Division of Catalysis Science and Technology Travel Award (2022)

AIChE Catalysis and Reaction Engineering Division Travel Award (2021)

Outstanding Graduate Student Instructor – UC Berkeley (2021)

Charles Bonilla Award for Outstanding Academic Merit – Columbia University (2019)

Goldwater Scholarship (2018)

Selected Publications: (4 of 20)

1. Corpus, K. R. M. ^‡, Bui, J. C.^‡, Limaye, A. M., Pant, L. M., Manthiram, K., Weber, A. Z., & Bell, A. T.* Coupling covariance matrix adaptation with continuum modeling for determination of kinetic parameters associated with electrochemical CO₂ Joule (2023).
2. Bui, J. C., Lees, E. W., Pant, L. M., Zenyuk, I. V., Bell, A. T., & Weber, A. Z.* Continuum modeling of porous electrodes for electrochemical synthesis. Rev. (2022).
3. Bui, J. C., Kim, C., Weber, A. Z. & Bell, A. T.* Dynamic boundary layer simulation of pulsed CO₂ electrolysis on a copper catalyst. ACS Energy Lett. (2021).
4. Bui, J. C., Digdaya, I., Xiang, C., Bell, A. T. & Weber, A. Z.* Understanding multi-ion transport mechanisms in bipolar membranes. ACS App. Mat. and Interfaces (2020).