Dr. Christopher Bohn, National Research Council – Energy Research Group
Seminar Abstract
Chemical looping is a new energy approach that permits combustion of fossil fuels with inherent capture of carbon dioxide and can achieve thermal efficiencies >50 %. I present results on the development of iron-based oxygen carriers with excellent redox stability and rapid kinetics over repeated cycles. Using experimental and numerical techniques, I demonstrate that these carriers can also be used to generate high purity hydrogen from coal or biomass while simultaneously capturing carbon dioxide for sequestration.
Iron oxide is also one of the few binary oxides capable of exceeding a solar to hydrogen efficiency of 10 % in photoelectrochemical water splitting. I show that activating n-type dopants in iron oxide by thermal annealing improves conductivity and photocurrent by three orders of magnitude. Further strategies for enhancement including plasmonic electrodes and nanostructuring are also presented.
Biography
Christopher Bohn is a National Research Council (NRC) Postdoctoral Research Associate in the Energy Research Group. He received his B.S.E. degree with honors in Chemical Engineering from Princeton University, and a Ph.D. in Chemical Engineering and Biotechnology from the University of Cambridge, UK. His doctoral work, supported by a Gates Cambridge Scholarship (you could cut this), focused on the synthesis and characterization of iron-based materials for use in carbon dioxide capture and hydrogen production. At the National Institute of Standards and Technology Nanolab, Chris is working with Veronika Szalai on integrating new concepts from optics and catalysis to enhance the efficiency of photoelectrodes for solar water splitting.