(4ev) Scalable Synthesis of Tailorable Nano- and Micro-Scale Materials for Energy Applications

The exploration of nanoscale materials has led to myriad of technological advances in the last several decades, especially in the energy sector. These materials, particularly at the nanoscale, have unique mechanical, optical, and electrical properties that lead to exemplary performance in applications such as energy harvesting and storage, fuel production, catalysis, and drinking water production using solar steam. High-performance nanomaterials offer an opportunity to address concerns around increased worldwide energy demands through novel application in the energy sector. While many such materials have been synthesized and reported in the literature, the synthesis process is generally expensive and low-yield, with minimal scale-up opportunities.

My research interests are in the study and development of scalable processes for synthesizing nanomaterials, particularly for use in electrochemical energy storage and catalysis. I aim to 1) design scalable synthesis processes for nanoscale materials through a mechanistic understanding of synthesis phenomenon, 2) investigate the performance of the materials in electrochemical catalysis and energy storage applications, and 3) using reaction modeling coupled with aerosol dynamics to study synthesis phenomena in the reactor for scalability. I plan to build and study aerosol and particle-based systems which provide advantages over solution-based processes for the controllable synthesis of tailorable nanomaterials. Through proper process design & control, materials with unique morphologies (spherical, hollow, wires, columns, etc.), low dimensionality (0-dimensional through 3-dimensional), and tailored composition (doped materials, solid solutions, layered compositions).

Aerosol reactors are widely used for industrial scale material synthesis, including carbon black, fused silica for pharmaceuticals, and optical fibers. At the academic level, many pyrolysis and “spray” processes are fundamentally aerosol reactors. Additionally, nonequilibrium systems, such as nonequilibrium plasmas, can be used to synthesize meta-stable materials, catalysts, and high-value semiconductor materials. Aerosol processes offer many advantages over traditional solution-based synthesis routes as they are single or few step processes that do not produce any liquid by-products and offer easier particle collection. In these reactors, each particle acts as its own microreactor, allowing for better control over the reaction and resultant material. Particle formation, growth, and particle-particle or particle-gas interactions are key phenomena that, once understood, can be manipulated to tailor the resultant nanomaterials.

My background has prepared me to work in the interdisciplinary research area between chemical engineering and materials science to develop scalable processes for material synthesis to address the pressing needs for new energy technologies. In this poster, I present a variety of processes that I intend to study for the synthesis of tailorable materials at the nano- and micro-scales.

Research Interest

My PhD work has focused on the study of aerosol reactors and the fundamental phenomena occurring during material synthesis. Aerosol-based reactors provide unique opportunities to control and tailor properties of the final materials using easily controlled system parameters. For example, aerosol chemical vapor deposition (ACVD) allows for the deposition of structured metal oxide thin films by controlling reactor temperature and precursor flow rates. Additionally, doped-metal oxide thin films may be synthesized by introducing two precursors simultaneously. During my graduate work I have used ACVD to synthesize SnO₂, TiO₂, and Cu-doped TiO₂ films for use as battery electrodes in lithium-ion battery coin cells. Electrospray can be used to form mono-dispersed nano-droplets, which I have used to deposit a metal-organic framework coating material. Finally, furnace aerosol reactors can be used to synthesize particles ranging from the nano- to micro-scales by controlling precursor concentrations. Additionally, hollow particles can be synthesized using knowledge of the reaction phenomena and tailoring system conditions. My graduate work has focused on the application of materials synthesized using these processes in energy storage, in the form of lithium-ion batteries and lithium-sulfur batteries.

As a postdoctoral fellow, my work focused on improving the floating catalyst chemical vapor deposition (FCCVD) process for the synthesis of single-walled carbon nanotubes. As part of this project, I redesigned the catalyst generation system to provide better control of catalyst size and concentration. Additionally, I have applied my knowledge of aerosol dynamics to the catalyst formation and growth processes to better predict particle size throughout the reactor as a function of reactor parameters.

Teaching Philosophy & Experience

Teaching is about more than presenting information to your students, it is about helping students develop their knowledge base, critical thinking skills, and confidence to address complex problems. I believe that this begins by helping students develop a strong grasp on the fundamental principles of chemical engineering. Doing this provides students a foundation to fall back on when presented with challenging new problems during both their time in school and later in their careers. Providing students with a solid knowledge foundation will also help build their confidence, which will also help them communicate and present their knowledge, critical skills I wish to help foster for my students. Looking back on my time as an undergraduate, most of my major classes had open book exams, putting the focus was on understanding concepts and being able apply them to new problems instead of remembering the exact form of equations. I would like to implement a similar focus in my future classes.

I endeavor to be a dynamic and engaging instructor that focuses on helping students understand the critical concepts of their coursework. Creating a positive classroom environment and reducing student’s stress by taking emphasis off large exams will foster an environment that encourages student learning. I will help students develop important skills, involving teamwork and effective communication, in addition to technical knowledge needed for a successful career. Chemical engineering is undoubtedly a difficult field of study, which makes guiding students through their education one of the most exciting and rewarding roles as an educator. My main goal will be to train capable, independent, and confident engineers that will be able to use their knowledge and creativity to solve any engineering problem they face.

Through my experience as a teaching assistant and research mentor I learned how beneficial these roles were to my own understanding of the course work or research area. During my time as a graduate student, I have been a teaching assistant for undergraduate Engineering Analysis of Chemical Systems, Mass Transfer Operations, and Process Control Lab. Through these experiences I have covered the range of teaching new chemical engineering students the basics of mass and energy balances to helping senior students design their experiments in Process Control Lab. Additionally, in the research setting I have mentored several undergraduate students and junior graduate students. Working with students with various levels of experience in research has shown me the importance of effective communication is and has taught me how to best organize my own efforts and those of other researchers. I feel prepared to teach any of the undergraduate chemical engineering courses and would be particularly interested in teaching or developing a course on the place of chemical engineering in the energy field.