Researchers at UVA and James Madison University have teamed up to test economically viable materials for hydrogen fuel cells, a promising option to decarbonize the transportation and logistics sectors.

Right now, vehicles powered with hydrogen are still relatively uncommon. To make them more widespread, fuel cells that generate electricity from hydrogen must become more efficient and affordable.

Petra Reinke, professor of materials science and engineering at UVA’s School of Engineering and Applied Science, and Ashleigh Baber, associate professor of chemistry at James Madison University, earned a 4-VA grant to conduct experiments with new, more affordable materials that promise to realize the vision. They are exploring whether new 2D materials can replace platinum in the fuel cells’ innerworkings.

The platinum reacts with the hydrogen as part of the electrochemical process that generates electricity, but the precious and expensive metal limits wide commercial adoption of this technology.

Reinke and Baber’s research will inform the search for new, platinum-free metal materials that could replace or reduce the amount of platinum required while generating the same amount of electricity.

Specifically, they are working with a class of 2D semiconducting materials called transition metal dichalcogenides as the catalyst material for hydrogen oxygenation. Transition metal dichalcogenides are 2D materials coveted for a wide range of applications as catalysts and electrocatalysts in energy systems, water splitting and hydrogen production. Transition metal dichalcogenides, or TMDs, get their name from their composition: a transition metal such as molybdenum, tungsten or niobium sandwiched between an element from the oxygen family, a chalcogenide such as sulfur or selenium.

“To achieve peak catalytic performance, we need to understand the connection between surface reactions with relevant molecules and the properties of the TMDs themselves,” Reinke said.

Whereas published studies document the use of transition metal dichalcogenides, the chemistry-materials connection for catalytic applications is still not comprehensively understood. Reinke and Baber’s research fills this critical knowledge gap using surface chemistry methods to study molecule bonding on TMD layers and materials science to control and measure the defect inventory and local electronic structure.

“Imagine your molecule arrives at a surface,” Reinke said. “You need the right surface, a defect, to push the molecule in the right direction. Our cross-disciplinary approach will lead us to defect engineering for TMD peak performance based on a fundamental understanding of molecule-TMD interactions.”

Their study will test the hypothesis that chemical bonding of methanol, ethanol and water molecules and their reaction products can be correlated to a defect inventory defined by defect and step edge density, electronic and geometric structure and spatial distribution. They plan to control the defect inventory through thermal annealing and ion and plasma irradiation of the transition metal dichalcogenide.

The exploration of molecular adsorption, reactivity, and desorption over transition metal dichalcogenides will provide insight into the structure/activity relationship, allowing greater control over the materials. Successful experimentation can lead to a future predictive tool for defect engineering to optimize the materials’ performance.

Reinke and Baber designed the research project with undergraduate and graduate students in mind. For example, their students conducted a baseline study to establish protocols for sample transport and data analysis, working with pristine TMDs where only a few defects and step edges are present. Now the students are conducting experiments to control the introduction of defects and modeling ion-surface interactions, the first step toward quantifying and controlling defects.

JMU and UVA student group photo

From left to right:  Charles Grant (JMU), Lyssa Garber (JMU), Jacob St. Martin (UVA), Ava Galgano (JMU), Clayton Rogers (JMU) and Jessie Berry (JMU).