ChBE Seminar Series: Feng Jiao
Tuesday, September 16, 2014
11:00 a.m.-12:15 p.m.
Room 2108, Chemical and Nuclear Engineering Bldg.
Professor Jeffery Klauda
Nanoporous Materials for Energy Applications
Department of Chemical and Biomolecular Engineering
University of Delaware
Energy conversion and storage are more important today than at any time in human history. In our lab, we combine our expertise in catalysis, materials science and electrochemistry, and by doing so are able to address the most exciting scientific challenges that occur in the field of energy conversion and storage. In this seminar, I will present our recent work on developing highly selective and robust CO2 reduction electrocatalysts. Reduction in greenhouse CO2 emissions from fossil fuel utilization is critical for human society. Ideally, one would like to convert CO2 produced in power plants, refineries and petrochemical plants to fuels or other chemicals through renewable energy utilization. The selective conversion of CO2 to CO is a promising route for clean energy. The CO product can be used as feedstock in the Fischer-Tropsch process, a well-known and well-characterized process that has been used in industry to produce chemicals and synthetic fuels from syngas (CO + H2) for many decades. By coupling the catalytic reduction of CO2 to CO with the Fischer-Tropsch process to produce synthetic fuels and industrial chemicals, the estimated maximum reduction of atmospheric CO2 emissions is 40%. Silver is an attractive CO2 reduction electrocatalyst, because it is able to reduce CO2 to CO with a good selectivity (~81%) and it also costs much less than other precious metal catalysts. In this talk, we will present a nanoporous silver (np-Ag) catalyst, which is able to reduce CO2 electrochemically to CO in a highly efficient and selective way. Not only the porous structure creates an extremely large surface area for catalytic reaction, but also the curved internal surface generates a large number of highly active step sites for CO2 conversion, resulting in an exceptional activity that is over three orders of magnitude higher than that of the polycrystalline counterpart at a moderate overpotential of < 500 mV. More importantly, such a remarkable activity for CO2 electroreduction has been achieved with a CO Faradaic efficiency of 92%.
Lu, Q., Rosen, J., Zhou, Y., Hutchings, G. S., Kimmel, Y. C., Chen, J. G., & Jiao, F.* A selective and efficient electrocatalyst for carbon dioxide reduction. Nature Communications 5:3242 (2014).