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MichiganState University Science at the Edge Engineering Seminar *February 21^st , 2014* 11:30 a.m. Room1400 Biomedical and Physical Sciences Building Refreshments served at 11:15 a.m. *Enrique Gomez* Chemical Engineering The Pennsylvania State University */From molecules to devices: self-assembled organic photovoltaics/* Abstract Organic electronic materials have the potential to impact almost every aspect of modern life including how we access information, light our homes, and power personal electronics.Unfortunately, weak intermolecular interactions and disorder at junctions of different organic materials limit the performance and stability of organic interfaces and hence the applicability of organic semiconductors to electronic devices.Our approach has focused on utilizing block copolymer architectures --where critical interfaces are controlled and stabilized by covalent bonds-- to demonstrate that self-assembled soft materials can provide the hierarchical structure needed for high-performance organic electronics.For example, we have demonstrated control of donor-acceptor heterojunctions through microphase-separated conjugated block copolymers to achieve 3% power conversion efficiencies in non-fullerene photovoltaics.Characterization through X-ray scattering and electron microscopy reveals that the efficient performance of block copolymer solar cells is due to self-assembly into mesoscale lamellar morphologies with primarily face-on crystallite orientations. Although inferior in performance to inorganic and champion polymer/fullerene solar cells, the significant photovoltaic response of block copolymer devices provides the initial results needed to accelerate the design of next-generation materials.Control of interfacial morphologies afforded by the block copolymer architecture facilitates theory efforts, such that we can utilize the combination of Density Functional Theory, Molecular Dynamics simulations and polymer theory to predict donor-acceptor block copolymers with control of charge transfer processes. Bio Enrique D. Gomez received his B.S. in Chemical Engineering from the University of Florida in 2002 and his Ph.D. in Chemical Engineering from the University of California, Berkeley in 2007. After a year and a half as a postdoctoral research associate at Princeton University, he joined the faculty at the Chemical Engineering Department of the Pennsylvania State University in August of 2009. Enrique's research focus is on understanding how structure at various length scales affects macroscopic properties of soft condensed matter. In particular, the current emphasis of his research group is on the relationship between microstructure and electrical properties in the active layers of organic thin film transistors and photovoltaics.Enrique has been awarded multiple awards, including a Visiting Scientist Fellowship from the National Center for Electron Microscopy, the Ralph E. Powe Junior Faculty Award by the Oak Ridge Associated Universities, and the NSF CAREER Award. For further information please contact Prof. Christina Chan, Department of Chemical Engineering and Materials Science at [log in to unmask] Persons with disabilities have the right to request and receive reasonable accommodation. Please call the Department of Chemical Engineering and Materials Science at 355-5135 at least one day prior to the seminar; requests received after this date will be met when possible.