Awards
2024-2025
Debasree Mandal
- Analytical Chemistry Younger Chemists Conference Travel Grant
Elise Freezer
- Chemistry Summer Research Award
Hyein Lee
- Bard CEC Graduate Student Fellowship
Thomas D. Pope
- Grant Wilson Award for Undergraduate Research
Elias Mondaca-Medina
- YCC Travel Grant from the ACS Division of Analytical Chemistry
Robert Gudgel
- Provost’s Graduate Excellence Fellowship
- Henze Teaching Award
Changhyun Ryu
- Bard CEC Student Fellowship
Sam Wenzel
- SEAC Best Poster Award
- ECS Symposium 2025 (Texas Section) Best Poster Award
He Zhang, Yang Tao, and Tamilselvi Gurusamy
- CEC travel grant
2023-2024
Yufei Wang
- Graduate School Dissertation Writing Fellowship
Sam Wenzel
- Henze Teaching Award
- Provost’s Graduate Excellence Fellowship
Elias Mondaca Medina
- Faraday Teaching Award
- Provost’s Graduate Excellence Fellowship
Principal Investigator
Postdoc Fellows
Dr. Donghoon Lim
Donghoon Lim is a South Korea–born scientist whose doctoral training centered on analytical chemistry and single-entity electrochemistry, with applications to electrocatalysts and biological systems. As a postdoctoral researcher in the Ren Lab, he integrates SECCM, SECM, and SICM with electron-microscopy analysis to probe biological processes and nanoscale electrochemistry. His current interests include single-cell/particle measurements and method development for scanning probe electrochemistry.
Email: donghoon.lim@austin.utexas.edu
Dr. Joshua Beeler
Josh received his Ph.D. from the University of Utah under the supervision of Prof. Henry S. White in 2025. His doctoral studies focused on method development and mechanistic analysis for organic electrosynthesis. Josh also carried out undergraduate research at Indiana University – Bloomington under the guidance of Prof. Dennis G. Peters and Prof. Stephen C. Jacobson. In the Ren lab, he is focusing on various applications of bipolar electrochemistry.
Email: joshua.beeler@austin.utexas.edu
Dr. Shuai Zhang
Shuai Zhang received her Ph.D. degree from Renmin University of China under the supervision of Prof. Meining Zhang in 2024. From 2024 to 2025, she was a research assistant in Zhang’s Lab. Her research interests were focused on single cell electrochemistry and biosensors. In Ren Lab, she will focus on SICM-based single-entity delivery.
Email: shuai.zhang@austin.utexas.edu
Dr. Mamta Dagar
Mamta earned her Ph.D. degree from the University of Rochester in April 2025 under the supervision of Prof. Ellen Matson. Her doctoral work focused on engineering the electrolyte system for designing improved redox flow batteries. To further pursue her interests in understanding electrochemical processes as relevant to energy storage and conversion, Mamta joined the Ren Group in May 2025, where she is working on metal extraction from seawater using bipolar electrochemistry.
Email: mamta.dagar@austin.utexas.edu
Dr. He Zhang
I received my Ph.D. from Changchun Institute of Applied Chemistry (CIAC), Chinese Academy of Sciences (CAS) & University of Science and Technology of China (USTC) under the supervision of Prof. Shaojun Dong in 2020. From 2021 to 2022, I was a research assistant in Dong’s Lab. My research interests were focused on enzyme-based bioelectrocatalysis, bio- photoelectrocatalysis, and biosensors. In Ren Lab, I will focus on single-entity electrochemistry.
Email: he.zhang@austin.utexas.edu
Graduate Students
Changhyun Ryu
Graduate Student (Aug 2022 – Present)
Changhyun Ryu is from South Korea and obtained his B.S. and M.S. degrees in Chemistry from Yonsei University in Korea. During those days, he focused on studying electrocatalysts for the carbon dioxide reduction reaction and electrodes for the lithium-air battery using scanning electrochemical microscopy and COMSOL Multiphysics simulation. In his free time, Changhyun Ryu usually plays sports or online games.
Email: CHRyu@austin.utexas.edu
Hyein Lee
Graduate Student (Aug 2022 – Present)
Hyein Lee received her B.S. and M.S. degrees in chemistry from Kyung Hee University, South Korea. Her research interest is in investigating mechanisms of nanomaterial electrocatalysis and in controlling the selectivity of electrocatalysis products by using surface resonance. She enjoys drawing with an iPad and exercising at the Gregory Gym in her spare time.
Email: hl29998@my.utexas.edu
Iván ElÍas Mondaca-Medina
Graduate Student (Aug 2022 – Present)
Education: Colorado College (2017-2021) B.A. Chemistry
During his undergraduate studies, Elías research focused on developing electrochemical sensors, using bipolar electrodes and molecular imprint polymers for the detection of lead and PFAS in drinking water. He joined the Ren lab in 2022. In his spare time, Elías enjoys long-distance running.
Email: iem453@austin.utexas.edu
Debasree Mandal
Graduate Student (Aug 2022 – Present)
Finished her Master’s from the Indian Institute of Technology, Bombay, India. Under the guidance of Prof. Subramaniam Chandramouli, she explored magneto-electrocatalysis for her master’s thesis. Now in Dr. Ren’s group, Debasree focuses on understanding nanoelectrochemistry. In addition to her constant interest in sports, she also enjoys drawing and watching movies.
Email: dm54732@my.utexas.edu
Sam Wenzel
Graduate Student (Aug 2023 – Present)
Sam Wenzel received his B.S. in Biochemistry from Florida State University in 2022. His undergraduate research under Dr. Robert Lazenby consisted of benchmarking bimetallic carbide nanomaterials as OER electrocatalysts, as well as fabricating low-cost, carbon-based nanoelectrodes using carbon pyrolysis techniques. In his spare time, he enjoys going to the gym, listening to music, cooking, and playing video games.
Email: sfw477@my.utexas.edu
Roberto García Carrillo
Graduate Student (Aug 2023 – Present)
Roberto received his B.S. in Chemistry and Nanotechnology from Tecnológico de Monterrey in 2021. His undergraduate research under Dr. Marcelo Videa focused on simulations of galvanostatic deposition of metallic nanoparticles. He then completed his M.S. in Nanotechnology in the same institution working in electrochemical single-entity characterization of bimetallic nanoparticles in 2023. In his spare time, he likes to play the violin and play videogames.
Email: roberto.garciacarrillo@austin.utexas.edu
Yang Tao
Graduate Student (Aug 2023 – Present)
Yang earned his B.S. in Chemistry from the University of Science and Technology of China (USTC) in 2023. During his undergraduate studies, he conducted research under the guidance of Prof. Yanxia Chen and Prof. Jun Huang, focusing on theoretical simulations of electrode-electrolyte interfaces and the mechanisms of HER electrocatalysts. Following that, he joined the Ren lab in 2023 to work on nanoelectrochemistry. In his free time, Yang enjoys watching movies, cooking, and browsing through the supermarket.
Email: yt6644@my.utexas.edu
Robert Gudgel
Graduate Student (Aug 2024 – Present)
Rob received his B.S. in Chemistry from the University of Texas at San Antonio in 2024. There, he conducted his undergraduate research under the advisement of Dr. Waldemar Gorski, focusing on the development of cost-effective electrode films to enhance H₂O₂ detection and modifying glucose test strips toward the electrochemical detection of disease-precursor enzymes. In his spare time, Rob enjoys hiking and exploring, collecting antiques, and going to history museums.
Email: robert.gudgel@austin.utexas.edu
Yerin Kim
Graduate Student (Aug 2025 – Present)
Yerin Kim received her B.S. in Chemistry and Nanoscience from Ewha Womans University in South Korea. She is currently interested in electrocatalysis, especially oxygen reduction reaction (ORR) on electrocatalysts. Her work focuses on understanding how surface states and potential-dependent interfacial structures influence catalytic activity and reaction pathways. Outside the lab, she enjoys running, hiking, and squash.
Email: yk22386@my.utexas.edu
Undergraduate Students
Thomas Pope
Undergraduate Student
The University of Texas at Austin (2023 – Current)
Email: tdp2276@my.utexas.edu
Elise Freezer
Undergraduate Student
The University of Texas at Austin (2024 – Current)
Elise Freezer is currently pursuing a Bachelor of Science in Chemistry, with a minor in Materials Science and Engineering, at the University of Texas at Austin. She joined the Ren Lab in 2024 as a sophomore in order to pursue her interest in nanoelectrochemistry. In her free time she enjoys sudoko, hiking, and other outdoor activities.
Email: ef22785@my.utexas.edu
Johan Martinez
Undergraduate Student
Johan is a Pre-Medical student pursing his Bachelor of Science in Chemistry with a minor in Business Administration. He joined Ren lab as a Freshman in 2024 to study SICM delivery techniques. For fun, he likes to play on his switch and workout.
Email: jim2369@my.utexas.edu
Ivan Negre
Undergraduate Student
Ivan Negre is pursuing a Bachelor of Science in Chemistry at the University of Texas at Austin. To pursue his interest in electrochemistry, he joined the Ren Lab in spring of 2025 as a sophomore. In his free time he enjoys watching shows, playing video games and reading books.
Email: iwn72@my.utexas.edu
Dara Cheng
Undergraduate Student
Dara Cheng is an undergraduate student studying Chemistry and Mathematics. She’s interested in modeling electrochemical systems.
Email: dc53555@my.utexas.edu
Ulan Sarolia
Undergraduate Student
Ulan is working towards a Bachelor of Science in Chemistry. He joined the Ren Lab to learn more about electrochemistry and its applications. In his free time, he plays sports like badminton, basketball, and ultimate frisbee.
Email: us2838@my.utexas.edu