Mrmes Goward Group

Our research group aims to apply advanced solid-state NMR techniques, in combination with electrochemical characterization, to the study of materials of interest as chemical power sources. Proton exchange membrane fuel cells (PEM-FC) and secondary lithium ion batteries provide environmentally friendly energy alternatives. As yet under-exploited is the unique advantage of solid-state NMR for investigating the protons in PEM-FCs, and the lithium ions in Li-ion rechargeable batteries, which can be thought of as the “work horses” of these two systems. Solid-state NMR is well known for its ability to provide site-specific information on structure and dynamics. Processes and interactions such as hydrogen-bonding, ionic conductivity, and polymer chain ordering or mobility can be effectively probed. In recent years, the field of solid-state NMR has experienced rapid technological and methodological growth, allowing a broader range of materials questions to be addressed. Our research extends the use of these powerful new methods to innovative, electrochemically-relevant materials in which structure-property relationships will be determined. As compared to solution-state NMR, where fast isotropic tumbling causes dipolar, quadrupolar, and chemical shielding anisotropies to be averaged, these interactions are retained in the solid state and thus provide a rich source of information. Advanced solid-state NMR methods, including high-resolution ¹H NMR achieved at high speed Magic Angle Spinning (>30kHz), 2D homonuclear double quantum NMR, heteronuclear multiple quantum NMR, and 2D exchange are used to characterize both structure and dynamics.