Recently developed dynamic nuclear polarization (DNP) nuclear magnetic resonance (NMR) spectroscopy instrumentation provides new opportunities to measure the compositions and structures of technologically important solid-state materials at the level of their atoms. Such capabilities yield new insights that are central to the design, development, and engineering of novel solid-state materials with promise for far-reaching societal or industrial impacts. Specific materials and applications under investigation include high-performance and low-carbon-footprint cements, catalysts for converting biofuels and natural gas to high-value liquid products, organic photovoltaic thin films and nanoscale semiconductors for solar energy conversion, battery and fuel cell materials for electrochemical energy generation and storage, and bio-inorganic solids for sustainable structural materials. Use and understanding of state-of-the-art DNP-NMR instrumentation by students contribute to their education and training across the chemical, physical, materials, and biological sciences. The analyses and applications provide interdisciplinary training that prepares students to address continually-changing energy, environmental, and other needs of society in the broadest of terms. Independent or collaborative access to the integrated DNP-NMR spectrometer by researchers at other regional, national, and international universities extend user base and benefits of the instrument beyond UCSB, in particular to regional partner groups at UC Berkeley, UC Irvine, UCLA, UC Riverside, and Cal Poly.
The DNP-NMR instrumentation provides an unprecedented combination of both high signal sensitivity and high spectral resolution for measuring molecular surface species that govern the functions of materials for a broad range of energy, structural, and environmental applications. Among the critical problems and challenges to improving the properties of such materials is the insufficient sensitivity of conventional methods, including NMR, especially for the detection of dilute or surface species. Integrated DNP-NMR measurements provide dramatic NMR signal enhancements of 2 orders of magnitude, resulting in time savings of up to 4 orders of magnitude over that achievable with previous state-of-the-art capabilities. The DNP-NMR instrument represents a breakthrough in molecular characterization that opens new opportunities to characterize and understand heterogeneous functional solids. The scope and goals of the research notably include materials with industrially relevant compositions, synthesized under industrially relevant conditions, and/or materials with low-surface areas or dilute or low-natural abundance species (e.g., 13C, 15N, 29Si, 77Se). The resulting DNP-NMR spectra and analyses are without precedent in the technical literature and enable, for the first time, the molecular-level characterization of complicated compositions and structures of material surfaces that till now have been entirely infeasible by conventional high-field NMR spectroscopy. Such solid-state DNP-NMR capabilities are expected to enable broad and transformative advancements in the materials and chemical sciences and become a standard for molecular characterization of complicated heterogeneous materials, whose surface functionalities are crucial to their properties, but whose molecular origins have previously been exceedingly challenging to establish.
