{"64952":{"#nid":"64952","#data":{"type":"event","title":"MSE Ph.D. Thesis Defense \u2013 Lei Yang","body":[{"value":"\u003Cp\u003E\u003Cstrong\u003EThesis Title:\u003C\/strong\u003E New Materials for Intermediate-temperature Solid Oxide Fuel Cells to be Powered\nby Carbon- and Sulfur- Containing Fuels\u003C\/p\u003E\n\n\n\n\u003Cp\u003E\n\u003Cstrong\u003EAbstract\u003C\/strong\u003E:\u0026nbsp; The demand for\nclean, secure, and renewable energy has stimulated great interest in fuel\ncells. Among all types of fuel cells, solid oxide fuel cells (SOFCs) offer\ngreat promise for the most efficient and cost-effective utilization of a wide\nvariety of fuels such as hydrocarbons, coal gas and gasified biomass. The\ncritical technical barrier to fuel flexibility is the vulnerability of the\nstate-of-the-art Ni-YSZ (yttria-stabilized-zirconia) anode materials to coking\nand sulfur poisoning. In addition, the high operating temperatures of SOFCs,\nstemming from the low ionic conductivity of the electrolyte materials and the\npoor performance of the cathode materials at lower temperatures, increase costs\nand reduce the system operation life. Therefore, the main objective of the\nresearch is to develop new electrolyte and electrode materials with high\nelectrical conductivity and electrocatalytic activity at low temperatures and\nto gain fundamental understanding of the interrelationships between lattice\nstructure, local atomic environment, bulk transport, surface property and\nelectrocatalytic activity. \u003C\/p\u003E\n\n\u003Cp\u003EFour research\nthrusts will be detailed in this presentation. First, a new electrolyte was\nshown to have the highest ionic conductivity below 750\u003Csup\u003Eo\u003C\/sup\u003EC of all\nknown electrolyte materials for SOFCs applications. Synchrotron-based X-ray\ndiffraction and Extended X-ray Absorption Fine Structure (EXAFS) were employed\nto investigate the lattice structure and local atomic environment. Second, when\nused in combination with Ni as a composite anode, it was shown to provide\nexcellent tolerance to carbon buildup (coking) and deactivation (poisoning) by\ncontaminants commonly encountered in readily available fuels. The mechanism\nresponsible for the enhanced electrocatalytic activity was unraveled by\nanalyzing the anode surfaces using Raman spectroscopy and Scanning Auger\nNanoprobe. Third, a simple, cheap surface modification of state-of-the-art\nNi-YSZ anode was developed that could be more readily adopted in the latest\nfuel cell systems, demonstrating direct utilization of hydrocarbons, CO and\ngasified carbon fuels. Advanced electron microscopy and spectroscopy, Raman\nspectroscopy and Density functional theory (DFT) calculations were used to\nunderstand the anodic reactions occurring on nano-islands and nanostructured\nmetal\/oxide interface. Last, a new composite cathode with simultaneous transport\nof proton, oxygen vacancies and electronic defects was developed for\nlow-temperature SOFCs based on oxide proton conductors. \u003C\/p\u003E\n\n\u003Cp\u003EIn conclusion,\nthis report represents a critical step toward an economically feasible fuel\ncell for utilization of a wide variety of readily available fuels as well as a\nunique mechanistic investigation of structure-property relationship and\nsurface- and interfaces-involved chemical and electrochemical reactions.\u003C\/p\u003E","summary":null,"format":"limited_html"}],"field_subtitle":"","field_summary":[{"value":"\u003Cp\u003EMSE Ph.D. Thesis Defense \u2013 Lei Yang\u003C\/p\u003E\u003Cp\u003EThesis\nTitle: New Materials for Intermediate-temperature Solid Oxide Fuel Cells to be Powered\nby Carbon- and Sulfur- Containing Fuels\u003C\/p\u003E","format":"limited_html"}],"field_summary_sentence":[{"value":"MSE Ph.D. Thesis Defense \u2013 Lei Yang"}],"uid":"27388","created_gmt":"2011-03-15 10:53:03","changed_gmt":"2016-10-08 01:54:22","author":"Bill Miller","boilerplate_text":"","field_publication":"","field_article_url":"","field_event_time":{"event_time_start":"2011-03-18T12:00:00-04:00","event_time_end":"2011-03-18T15:00:00-04:00","event_time_end_last":"2011-03-18T15:00:00-04:00","gmt_time_start":"2011-03-18 16:00:00","gmt_time_end":"2011-03-18 19:00:00","gmt_time_end_last":"2011-03-18 19:00:00","rrule":null,"timezone":"America\/New_York"},"extras":[],"groups":[{"id":"1238","name":"School of Materials Science and Engineering"}],"categories":[],"keywords":[{"id":"10802","name":"MSE_Interal_Event"}],"core_research_areas":[],"news_room_topics":[],"event_categories":[],"invited_audience":[],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[],"email":[],"slides":[],"orientation":[],"userdata":""}}}