{"632339":{"#nid":"632339","#data":{"type":"event","title":"PhD Defense by Matthew BoeBinger","body":[{"value":"\u003Cp\u003E\u003Cstrong\u003ETHE SCHOOL OF MATERIALS SCIENCE AND ENGINEERING\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003EGEORGIA INSTITUTE OF TECHNOLOGY\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003EUnder the provisions of the regulations for the degree\u003Cbr \/\u003E\r\n\u003Cbr \/\u003E\r\nDOCTOR OF PHILOSOPHY\u003Cbr \/\u003E\r\n\u003Cbr \/\u003E\r\non Monday, March 2, 2020\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003E11:00 AM\u003Cbr \/\u003E\r\nin MRDC 4211\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003Ewill be held the\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003EDISSERTATION\u0026nbsp;DEFENSE\u003Cbr \/\u003E\r\n\u003Cbr \/\u003E\r\nfor\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003EMatthew G.\u0026nbsp;Boebinger\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003E\u0026ldquo;\u003Cem\u003EIn Situ\u003C\/em\u003E\u0026nbsp;Examination of Nanoscale Reaction Pathways in Battery Materials\u0026rdquo;\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003ECommittee Members:\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003EProf. Matthew McDowell, Advisor, MSE\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003EProf.\u0026nbsp;\u003C\/strong\u003E\u003Cstrong\u003EJosh Kacher\u003C\/strong\u003E\u003Cstrong\u003E, MSE\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003EProf. Meilin Liu, MSE\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003EProf. Gleb Yushin, MSE\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003EProf. Ting Zhu, ME\/MSE\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003ERaymond Unocic, Ph.D., Oak Ridge National Laboratory\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003EAbstract:\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003EIn an effort to engineer less expensive and more energy-dense batteries, new materials must be developed to store and transport active ions reliably. However, the electrochemical reaction mechanisms of these materials must be understood and controlled to maximize reversibility during charge and discharge. This dissertation is focused on using \u003Cem\u003Ein situ\u003C\/em\u003E experiments, mainly the use of \u003Cem\u003Ein situ\u003C\/em\u003E transmission electron microscopy (TEM), to understand the nanoscale transformation pathways in different high-capacity electrode materials during reaction with Li\u003Csup\u003E+\u003C\/sup\u003E, Na\u003Csup\u003E+\u003C\/sup\u003E and K\u003Csup\u003E+\u003C\/sup\u003E ions. These materials, upon reacting with alkali-metal ions to form alloys or other compounds, often exhibit much higher specific storage capacities compared to conventional Li-ion battery electrode materials. In addition, these types of materials can also be used in lower-cost sodium- and potassium-based systems. They could therefore replace electrode materials in Li-ion batteries to enable higher specific energy batteries. However, the more substantial volumetric changes that these electrode materials undergo during reaction cause significant challenges, such as mechanical fracture of the active material and continuous growth of the solid-electrolyte interphase (SEI) on the surface of the anode particles leading to very low cyclability of these systems.\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003EFor the continued development of these battery systems, it is critical to understand both how the larger Na\u003Csup\u003E+\u003C\/sup\u003E and K\u003Csup\u003E+\u003C\/sup\u003E ions affect the nanoscale phase transformations during these reactions and how to engineer high capacity battery materials with high coulombic efficiency and longer cycle life. In the studies on the Cu\u003Csub\u003E2\u003C\/sub\u003ES and Fe\u0026shy;S\u0026shy;\u0026shy;\u003Csub\u003E2\u003C\/sub\u003E active materials, the effect larger alkali metal ions have on the reaction mechanisms of large-volume-change materials was examined. After extensive \u003Cem\u003Ein situ \u003C\/em\u003Eand \u003Cem\u003Eex situ\u003C\/em\u003E experiments the larger volume changes associated with the sodium\/potassium reactions indicated a more stable morphology for overall cycling behavior by demonstrating different reaction pathways and fracture behavior. In the study conducted on the Sb nanocrystals, it was demonstrated that small spherical particles naturally formed uniform internal voids that were easily filled and vacated during cycling. This was found to be due to the natural resilient oxide layer that formed after the first lithiation and prevents shrinkage during delithiation. Additionally, a model was developed that can serve as a tool to guide the creation of oxide or other types of shells that enable alloying materials to undergo voiding transformations \u003Cem\u003Ein situ\u003C\/em\u003E. All of these materials (Cu\u003Csub\u003E2\u003C\/sub\u003ES, FeS\u003Csub\u003E2\u003C\/sub\u003E and Sb) demonstrated interesting and counter-intuitive phase evolution and mechanical degradation behavior when reacting with the alkali ions of different sizes. These findings all indicated that large-volume-change materials could enable stable cycling performance for next-generation batteries, whether they be Li-ion or another battery chemistry that undergoes complex morphological changes.\u003C\/p\u003E\r\n","summary":null,"format":"limited_html"}],"field_subtitle":"","field_summary":"","field_summary_sentence":[{"value":"In Situ Examination of Nanoscale Reaction Pathways in Battery Materials"}],"uid":"27707","created_gmt":"2020-02-11 21:01:09","changed_gmt":"2020-02-11 21:01:09","author":"Tatianna Richardson","boilerplate_text":"","field_publication":"","field_article_url":"","field_event_time":{"event_time_start":"2020-03-02T11:00:00-05:00","event_time_end":"2020-03-02T13:00:00-05:00","event_time_end_last":"2020-03-02T13:00:00-05:00","gmt_time_start":"2020-03-02 16:00:00","gmt_time_end":"2020-03-02 18:00:00","gmt_time_end_last":"2020-03-02 18:00:00","rrule":null,"timezone":"America\/New_York"},"extras":[],"groups":[{"id":"221981","name":"Graduate Studies"}],"categories":[],"keywords":[{"id":"100811","name":"Phd Defense"}],"core_research_areas":[],"news_room_topics":[],"event_categories":[{"id":"1788","name":"Other\/Miscellaneous"}],"invited_audience":[{"id":"78761","name":"Faculty\/Staff"},{"id":"78771","name":"Public"},{"id":"174045","name":"Graduate students"},{"id":"78751","name":"Undergraduate students"}],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[],"email":[],"slides":[],"orientation":[],"userdata":""}}}