Collaborative Research: SusChEM: Molecular Design of Durable Lewis Basic Elastomeric Membranes for Clean Energy Conversion and CO2 Separation

NON-TECHNICAL SUMMARY: Heavy dependence on fossil fuels as an energy source has created the need for sustainable energy sources and technologies, as well as addressing the buildup of CO2 in the atmosphere. In fuel cells, the chemical energy stored in fuel is converted directly to electrical energy via electrochemical reactions without producing gases such as CO2. Recently, anion exchange membrane (AEM) fuel cells have been investigated as a promising sustainable-energy technology alternative to burning fossil fuels. Currently, the chemical instability of AEMs, loss of hydroxide conductivity, and deterioration of mechanical stability have been major obstacles to their successful applications. Current CO2 separation processes are not energy efficient, and CO2-selective membranes with better permeability and selectivity are needed. To address these issues, a research team composed of a synthetic polymer chemist, a physical polymer chemist, and a membrane scientist will conduct an interdisciplinary research and education program to advance our materials design based on durable elastomeric membranes for clean energy generation and CO2 separation technologies. The team of researchers will design new macromolecular materials to enhance performance of polymer membranes, followed by determining their structures and properties. Students will interact with experts in synthetic polymer chemistry, materials characterization, and membrane property evaluation and thus will be educated through multidisciplinary problem-solving approaches. In addition to basic research and education programs for students, outreach programs on clean energy and environmental sustainability will contribute to improving the scientific literacy of the local community and broaden the impact of this research on society. TECHNICAL SUMMARY: To date, the development of most membrane materials for anion exchange membrane (AEM) fuel cells and CO2 separation has relied on rigid polymers because of their good mechanical stability in dry states. However, elastic membranes with block copolymer nanostructure are more suitable for practical applications because they can better withstand the swelling and plasticization caused by water and CO2. In this collaborative project, the PIs will molecularly design polymer structures to enhance performance of polymer membranes for such applications. They aim to improve understanding of molecular-level relationships among polar groups, polymer architectures, nanophase-segregated morphologies, and polymer membrane properties (e.g., mechanical, thermochemical, ion transport, gas permeation), which may lead to the development of improved membrane materials for applications in alkaline fuel cells and CO2 separation processes. The outcomes of this SusChEM project will advance discovery and understanding for the design of next-generation polymer membranes for alkaline membrane fuel cells and CO2 separation.