(3hh) Variable Operation Accelerates Catalyst Degradation during Water Electrolysis

My goal is to develop transformative solutions for challenges in renewable energy, water resources, and the chemical industry. To achieve these goals, I incorporate principles of electrochemistry, catalysis, analytical chemistry, and chemical engineering into my research. This work encompasses a range of scales, from understanding catalytic interfaces at the atomic level to chemical processes.

With over eight years of research in electrocatalysis, analytical chemistry, and electrochemical engineering, my academic journey is supported by a strong publication record and successful project leadership. I’m also passionate about science communication and education. I’m committed to leading a research group dedicated to advancing sustainability in chemistry and engineering.

In this poster, I will cover my research on liquid alkaline water electrolysis (LAWE). This technology is essential in current decarbonization efforts, requiring durable catalysts. However, catalysts are vulnerable to the intermittent nature of renewable electricity necessary to power water electrolyzers. Understanding the reconstruction processes these materials undergo under variable operation is key to developing more robust technologies. We reveal the impact of intermittency and reverse currents on catalyst durability in LAWE. Through systematic in situ/operando characterization, we demonstrate that variable operation degrades catalytic films and accelerates corrosion.

Academic website

Selected Publications

Marquez, R.A., Mullins, C.B. et al., Tracking Local pH Dynamics During Water Electrolysis via In-line Continuous Flow Raman Spectroscopy. Submitted to ACS Energy Letters.

Marquez, R.A., Mullins, C.B. et al., Transition metal incorporation: electrochemical, structure, and chemical effects on nickel oxyhydroxide oxygen-evolution electrocatalysts. Energy & Environmental Science, 2024, 17, 2028-2045. Link

Marquez, R.A., Mullins, C.B. et al., A Guide to Electrocatalyst Stability Using Lab-Scale Alkaline Water Electrolyzers. ACS Energy Letters, 2024, 9, 2, 547–555. Link

Marquez, R.A., Mullins, C.B. et al., Getting the Basics Right: Preparing Alkaline Electrolytes for Electrochemical Applications. ACS Energy Letters, 2023, 8, 2, 1141–1146. Link

Full list of publications

Future Research

My research group will develop transformative solutions for the water-energy nexus through three main approaches:

• By understanding fundamental processes in electrochemical interfaces, leveraging my expertise in instrumental analysis to develop analytical platforms for advanced characterization.
• By characterizing electrochemical processes under industrially relevant conditions, fabricating functional devices and aiming to scale up promising technologies.
• By integrating electrochemical energy conversion and storage technologies into chemical processes, and collaborating with experts to consider interdisciplinary aspects into my research.

I aim to pursue three main research directions as an independent researcher:

#1: Harnessing the Ocean's Power to Capture CO₂ with Electrochemical Processes: This research aims to deepen the understanding of the chemical processes to capture carbon dioxide with seawater. Interfacial processes and local environments will be interrogated using advanced analytical methods developed by our group. New pH modulation strategies to capture carbon dioxide will be developed using redox carriers, inorganic electrodes, and membrane electrolyzers. Eventually, the impact of these chemistries on marine biogeochemistry will be evaluated.

#2: Decoding Catalyst Stability: At the Core of Efficient Chemical Processes: This proposal aims to uncover the fundamental forces driving the transformation and deactivation of electrocatalysts. Initial efforts will focus on studying the physical and chemical transformations of benchmark catalysts used in well-known technologies, such as water and sulfur electrolysis. Particular emphasis will be placed on understanding the influence of the reaction environment and corrosion. Insights from these studies will inform strategies to counteract catalyst deactivation, regenerate catalysts through self-healing mechanisms, and recover spent catalysts.

#3: Driving Innovation through Smart Manufacturing and Analytical Platforms: This research aims to develop smart, modular platforms for advancing materials discovery. Using electrocatalysis as a starting point, efforts will focus on creating and optimizing modules to synthesize, characterize, and test material libraries. Unique platforms for studying these materials will be developed, including in situ and operando characterization techniques, flow cells, and 3D printing technologies. In the long term, machine learning and statistical methods will be integrated to streamline data analysis.

Teaching Interests

I aim to equip students with the necessary tools and skills to succeed in life using seven pedagogical strategies:

• Practice creates skill. Students need to practice constantly to master their discipline. I will regularly assign tasks and homework, maintaining high expectations to meet real-world standards.
• Communication skills. Students need to communicate science effectively. My classes will encourage students to write across the curriculum.
• Active learning. STEM students must think, investigate, and create rather than memorize. My materials will expose students to real-world settings.
• Quantitative literacy. Students must learn to support their findings with quantitative evidence. I will rigorously teach and evaluate statistics, numerical methods, data analysis, and visualization.
• Continued support. My expertise with digital tools will allow me to record lectures and demonstrations, create animations, and share simulations.
• Interdisciplinary projects. My courses will integrate aspects from various fields to develop systems thinking and underscore the importance of cooperation in STEM.

I am interested in teaching transport phenomena, kinetics, catalysis, materials science, electrochemical engineering, and instrumental analysis. I propose an undergraduate course titled Electrified Chemical Processes and Separations that will expose students to electrochemical technologies used in industry. Graduate students will benefit from a course titled Energy Conversion and Storage focused on solid-state chemistry and device engineering concepts in fuel cells, electrolyzers, capacitors, and batteries.

Selected Awards

2025 CAS Future Leaders 2025, The American Chemical Society

2025 NAM29 Kokes Award, The North American Catalysis Society

2025 Energy Technology Division Graduate Student Award, The Electrochemical Society

2024 CATL-ChemCatBio Graduate Student Travel Award, The American Chemical Society

2024 Edward G. Weston Summer Fellowship, The Electrochemical Society

2024 #RSCPoster competition 2024 (1^st place, Energy category), The Royal Society of Chemistry

2024 Chemistry Department Service Award 2024, UT-Austin

2020-2025 Provost's Graduate Excellence Fellowship, UT-Austin