Researchers at the FAMU-FSU College of Engineering are exploring new uses for fuel cell membrane technology in areas such as sustainable energy and water treatment. Their recent study, published in Frontiers in Membrane Science and Technology, focuses on perfluorosulfonic acid polymer (PFSA) membranes. These membranes allow protons to pass through while blocking electrons and gases.
The research examined how boiling PFSA membranes—a common pretreatment—affects their performance for various applications. Daniel Hallinan Jr., a professor in the Department of Chemical and Biomedical Engineering and co-author of the study, said, “PFSA membranes are essential for making fuel cells function, but we wanted to examine understudied uses of this technology. The qualities that make them useful in one application may not be optimal for another purpose. Our goal was to understand how pretreatment affected the final material properties.”
PFSA membranes are designed to selectively move protons due to their chemical structure, forming thin sheets that act as filters. The amount of water inside these membranes is crucial because it influences ion movement. Boiling during production helps PFSA membranes absorb more water, which increases ion transport speed.
The team found that boiled (pretreated) membranes absorbed more water and conducted ions faster but were less selective—allowing more unwanted substances through. Untreated membranes had slower conductivity but better selectivity. Co-author Youneng Tang, associate professor in the Department of Civil and Environmental Engineering, explained: “If you want speed, pretreatment is helpful. If you want precision, pretreatment might hurt performance. Understanding how this process works will help engineers optimize membrane selection and pretreatment for specific applications.”
Researchers measured several key properties including permeability, water uptake, salt partitioning, and conductivity—factors important for technologies like flow batteries and lithium extraction.
Beyond fuel cells, PFSA membranes have potential roles in mineral harvesting from desalination brine (such as extracting lithium used in batteries), redox flow batteries for renewable energy storage systems by improving rapid ion transport efficiency, and electrochemical reactors that convert carbon dioxide into fuel.
Sebastian Castro, a former undergraduate at FAMU-FSU now pursuing doctoral studies at New York University and co-author of the study stated: “Membranes are crucial in electrochemical systems, serving to separate substances in the presence of an electric field. A deeper understanding of these membranes will enhance the viability of large-scale electrochemical processes. This work contributes to global efforts to improve renewable energy technology, making it more efficient and sustainable, ultimately providing better access to clean and affordable energy for everyone.”
Graduate student Dennis Ssekimpi also contributed as a co-author on this project. Support came from Florida State University as well as from the National High Magnetic Field Laboratory’s Research Experiences for Undergraduates program.
