Meet CTC: Sagar Udyavara

May 22, 2020 -- Sagar Udyavara is a fifth-year chemical engineering Ph.D. candidate in the Neurock group. Sagar completed his undergraduate degree in chemical engineering from the Institute of Chemical Technology (ICT) in Mumbai, India.

Sagar is currently investigating the fundamental chemistry behind the electro-organic synthesis of pharmaceutical and other organic intermediates. Electro-organic synthesis is a new area of organic synthesis that typically consists of the synthesis of organic chemicals using electricity as a tool to tune the chemical reactions to selectively produce organic chemicals and intermediates. The Neurock group is collaborating with synthetic and physical chemists from the University of Utah and the Scripps Research Institute to develop new, safe, sustainable, and scalable electrochemical routes for the synthesis of pharmaceutical intermediates. Most of the currently-used reactions that are used in pharmaceutical companies to synthesize new potential drug candidates involve the use of toxic and costly organic reagents, making the process challenging to scale. For a process to be scalable, the same chemical that is synthesized in the lab in milligram quantities needs to be produced at a larger scale using the same technique, while also having minimal technical difficulties or safety issues. Through collaboration with experimentalists, Sagar hopes to find a new way of synthesizing these organic intermediates using electrochemistry, which would make the process easily scalable and would also speed up the development of new pharmaceutical drug candidates.

For his research, Sagar uses quantum chemistry software packages to run DFT-based optimizations and molecular dynamics simulations to simulate the chemistry occurring for a specific reaction. He uses the Vienna Ab initio Simulation Package, better-known as VASP, for simulating heterogeneous systems and Gaussian for simulation of homogeneous systems. To simulate electrochemical systems, where the reactions occur at fixed potentials, the energies need to be determined at a constant potential rather than constant electrons. For this, Sagar uses the double-reference method, which was developed by previous members in the Neurock group.

In his spare time, Sagar likes reading books, especially biographies and autobiographies about successful people and their views on topics in everyday life, including economics, politics, psychology, history, and health. He also enjoys outdoor activities such as running, biking, and racquet sports like badminton and tennis.

How did you become interested in studying chemistry, and what gets you the most excited about your field?

My interest in chemistry goes back to my chemistry lab experience in high school. We did exciting experiments such as acid-base titrations using indicators and burning different metals to see different colored flames. I found that experience to be visually stimulating and I started to become interested in chemistry. 

While back then I was naive and thought it was just a “cool” subject to study, over the course of my undergraduate and graduate experience, I began to see the influence chemistry has on improving our standard of living. Everything we see around us has some aspect of chemistry involved, whether it is plastics, fertilizers, or pharmaceutical drugs. There are so many possibilities in the future to apply chemistry knowledge when coming up with new and sustainable alternatives to the current processes. Some examples are converting biomass to fuels and chemicals, harnessing renewable energy from the sun to synthesize back chemicals from carbon dioxide, or recycling and upcycling of plastics in order to maintain a balance between the needs of mankind and that of the environment. Contributing to these new developments gets me excited about being in the chemistry field.

Why did you choose the University of Minnesota, and what led you to join your current research group?

When I decided to apply for graduate programs, the UMN was one of the top universities on my list because it was well known and recommended by the professors, as well as alumni, at ICT. The UMN also has one of the best and most varied chemical engineering programs in the world. Since doing research was relatively new to me back then, I thought that joining the UMN would give me the flexibility to interact with different professors who are well respected in their field and then accordingly gauge my interest in different areas of research.

In my undergrad, I particularly liked the subjects of catalysis and chemical reaction engineering and found it to be applicable in large scale chemical industries, such as oil, gas, and petrochemicals. Therefore, when I joined the UMN, I came with an initial bias of working with someone in the catalysis field. While I never had my mind on doing computational research (actually, I never even knew about this particular field before joining UMN), I ended up joining Prof. Neurock’s group, particularly because the research in his group allowed me to visualize the chemistry that is happening on a molecular level. I was always fascinated by understanding the “why” behind the chemistry, and the Neurock group allows me to answer that question.

What is your favorite part about living in the Twin Cities?

My favorite part about living in the Twin Cities is the scope of recreational and entertainment activities that the Twin Cities provides with its various different bike trails, parks, lakes, and restaurants. The Stone Arch bridge, which is located near the university, is my favorite attraction and is a constant in my biking and running routes.

What do you enjoy most about your research? What has been your most interesting or surprising finding so far?

The thing that I enjoy most about my research is collaborating with experimentalists to understand the fundamentals behind the chemistry of the process that is taking place. We can then work together to come up with predictions for better reagents, materials, or catalysts for the given application. I personally find this experience to be gratifying.

The most exciting finding so far was in the project I did with Prof. Andre Mkhoyan, who is also in the Chemical Engineering and Material Sciences (CEMS) program. We were looking into understanding the effects that different metals have on the interface structure of metal-MoS₂ contacts, which form an integral part of MoS₂-based devices. These devices are being considered as a possible substitute to silicon-based transistors, which make up a crucial component of our computer processing chips. MoS₂, which is an inorganic compound composed of molybdenum and sulfur, can be used to produce even smaller transistors than what is possible currently with silicon, so more transistors could be packed in a unit area, which would increase the computing capacity. However, before MoS₂-based transistors can be used, their performance needs to be comparable to the currently used Si-based transistors. To do this, we need to understand the feature that currently poses a significant limitation in its performance – the interface of the metal-MoS₂ contact.

Through the Mkhoyan group’s analytical experiments and our simulations, we were able to show why titanium, a metal which previous theoretical studies predicted would give better performance, fundamentally cannot give improved performance because of its high reactivity upon initial contact, which disrupts the MoS₂ surface. The incorrect predictions previously made were due to limitations in the previous models used, which our models helped overcome. We were then able to appropriately screen different metal contacts and narrow down the search to a few select metals. One of these metals, indium, was experimentally shown to give improved performance, better than Ti, bringing us closer to the application of these MoS₂-based devices. It was interesting to see how different pieces of experimental and computational data could be pieced together to narrow down the search from a vast list to a few promising materials that can be tested experimentally. This accelerates the search for better materials.

What are you most proud of about your academic career so far, and what’s one thing you’d like to achieve in the future?

Throughout my academic career, I have been given various different projects spanning different areas of research. I am proud of the fact that I have been able to navigate through these many different collaborations and research areas and help collaborators better understand their chemistry.  The work that I am currently doing involves executing pre-made codes to run computer experiments. In the future, I would like to be on the other side, where someone could benefit from code or a program that I played a role in developing.

What drives you to be a better scientist?

There are always new problems emerging, along with many challenges that already exist, around us in healthcare, sustainability, and the environment that need to be solved. There is a constant expectation from the general public towards scientists to come up with solutions to solve these problems. This intrinsic motivation to be a better scientist is continuously upheld by my group members, my advisor, and my friends who regularly drive me to be a better version of my present self.

What advice do you have for aspiring scientists?

Learn, learn, and learn! To put it in the words of Satya Nadella (CEO of Microsoft), “I fundamentally believe that if you are not learning new things, you stop doing great and useful things.” A scientist is driven by curiosity and a desire to learn. I would advise future scientists to continually learn and never stop learning - not just about their particular field, but about other areas as well. The best out of the box ideas come when you expand and broaden your horizons and don’t stay constrained in your thought process.