ANN ARBOR, MI
The Materials Research Department at Toyota Research Institute of North America (TRINA) along with the National Institute of Standards and Technology (NIST) have have uncovered how ionic liquids (ILs) influence the microscopic structure and function of catalyst inks used in proton exchange membrane fuel cells (PEMFCs). Their findings, published in Macromolecules, provide critical insights that could lead to more efficient and durable fuel cell designs.
Using contrast variation small-angle neutron scattering (CV-SANS), the team analyzed how ionomers—polymeric proton conductors—interact with Pt/C catalyst particles in the presence of different IL formulations. The study revealed that IL composition alters the spatial distribution and association of ionomers within the ink. One particular IL, [BMIM][C4], showed strong binding with both the ionomer and catalyst surfaces. While this may improve dispersion stability, it also reduced the number of accessible platinum catalytic sites—ultimately leading to diminished fuel cell performance.
These structural insights connect molecular interactions within catalyst inks to real-world electrochemical performance, offering a pathway to rational ink formulation. By tailoring IL chemistry, researchers can now better design PEMFC inks that balance structural integrity with maximum catalytic efficiency. TRINA’s work sets a foundation for next-generation fuel cells with improved power output and longer operational lifespans.
Please see the complete work published in Macromolecules
