Designing Efficient Platinum-Free Electrocatalysts for Oxygen Reduction Reaction

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1132777LinicThe proposal represents a serious attempt at developing an approach to surmounting the most serious problem with low temperature H2 fuel cells. The slow kinetics of the oxygen reduction reaction at the cathode significantly reduces the efficiency obtained. To alleviate this, platinum electrocatalysts have been used. Although the negatives of high over-potential and Pt expense are inherent, platinum is one of the few metals stable in the high acid environment conventionally used. The acid-compatible polymer membranes needed for the fuel cell device were developed, so PEM fuel cells represent state-of-art devices, but with significant drawbacks.PI Suljo Linic from the Chemical Engineering Department at the University of Michigan offers a possible way around these issues. There have been adequate improvements in hydroxide membrane technology which opens the basic as opposed to acidic operating environment to consideration. Many more metals are stable in basic media, so the cost factor or even presence of Pt may be open to review. As a basis, Linic has done some preliminary experiments and computations on various metal surfaces in basic operating media, and postulates some differences in rate limiting steps which govern over-potentials on the various metal surfaces. He hypothesizes that specific Ag surfaces or Ag overlayer surfaces may help alleviate the over-potential issue in addition to replacing expensive Pt. He proposes some specific surface experiments and computational complements to investigate the validity of the hypotheses. Positive results may lead to a revitalization of H2 fuel cells and the use of H2 in certain fuel situations, which represents large technical impact potential. The broader educational and outreach components were a mixture of traditional and new approaches as proposed by Linic. The PI proposes to use social delivery media vehicles, such as YouTube, as a means of outreach to the high school and college audience. This approach builds on similar successful scientific outreach programs. One may argue with the likelihood, but it is basically another experiment that will be a part of the project. The students at the University who become involved in this project will definitely benefit from constructive integration of nanoscience and electro-catalysis.