Bulletin of the American Physical Society
78th Annual Meeting of the Southeastern Section of the APS
Volume 56, Number 9
Wednesday–Saturday, October 19–22, 2011; Roanoke, Virginia
Session DD: Advances in Energy |
Hide Abstracts |
Chair: Bruce Vogelaar, Virginia Polytechnic Institute and State University Room: Crystal Ballroom DE |
Thursday, October 20, 2011 1:30PM - 2:00PM |
DD.00001: Photonic Structuring of Bulk Heterojunction Organic Solar Cells Invited Speaker: The major challenge in solar cell technology dwells in achieving an efficient absorption of photons with an effective carrier extraction. In all cases, light absorption considerations call for thicker modules while carrier transport would benefit from thinner ones. This dichotomy is the fundamental problem limiting the efficiencies of photovoltaics, especially promising low-cost polymer solar cells. We present experimental and theoretical solutions to this problem applying photonic crystal nanostructuring in bulk heterojunction solar cells made of poly-3-hexylthiophene:[6,6]-phenyl-C61-butyric acid methyl ester (P3HT:PCBM). We discuss theoretical models of optical absorption that occur for the photonic design that result in a 22{\%} enhancement over a conventional planar cell. We also calculate the local exciton creation profile within the photonic crystal structure to show nanopatterning also reduces carrier transport length. Finally, experimental results are presented that follow the theoretical predictions along with our nano fabrication method to show this approach can be used to produce improved large-area nanostructured P3HT:PCBM solar cells. [Preview Abstract] |
Thursday, October 20, 2011 2:00PM - 2:30PM |
DD.00002: Advances in Polymer-Fullerene Photovoltaic Devices Invited Speaker: Polymer solar cells are of high interest due to their potential as efficient, lightweight, large area, flexible renewable energy sources. The basic mechanism for the photovoltaic effect in polymers consists of transfer of a photoexcited electron from the polymer donor to a fullerene electron acceptor followed by transport of the electron and hole through the acceptor and donor,, respectively, to the opposite electrodes. Polymer photovoltaic efficiencies can be increased by utilizing improved materials as electron donors and acceptors as well as by controlling the nanoscale morphology of the thin film devices. The highest efficiencies ($\sim $7{\%}) obtained thus far utilize a nanoscale polymer-fullerene blend referred to as a bulk heterojunction, which undergoes phase separation on the 10 nm length scale in order to facilitate charge transfer from the photoexcited polymer to the fullerene electron acceptor. More organized geometries that maximize the majority carrier materials at the respective electrodes could lead to enhanced efficiencies. In one approach, thermal interdiffusion of an initial bilayer of the donor and acceptor materials can be employed to create a concentration gradient in order to optimize both the charge transfer and charge transport processes. This presentation will overview the state-of-the-art in polymeric solar cells and describe the development of thermally-interdiffused concentration gradient geometries as an alternative route towards increased efficiencies. [Preview Abstract] |
Thursday, October 20, 2011 2:30PM - 3:00PM |
DD.00003: Nuclear Energy: Challenges and Directions Invited Speaker: There are many myths regarding nuclear energy. Nuclear energy provides many advantages but like all other power generation methods it has some drawbacks. There have been some serious accidents involving nuclear power generation with the most recent occurring at Fukushima Daiichi. What role will nuclear energy play in the future? What are the challenges of the nuclear landscape as we move forward? Are there changes in policy or technology that should be considered? A vision of nuclear energy will be provided in an attempt to address these upcoming opportunities and challenges. [Preview Abstract] |
Follow Us |
Engage
Become an APS Member |
My APS
Renew Membership |
Information for |
About APSThe American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics. |
© 2024 American Physical Society
| All rights reserved | Terms of Use
| Contact Us
Headquarters
1 Physics Ellipse, College Park, MD 20740-3844
(301) 209-3200
Editorial Office
100 Motor Pkwy, Suite 110, Hauppauge, NY 11788
(631) 591-4000
Office of Public Affairs
529 14th St NW, Suite 1050, Washington, D.C. 20045-2001
(202) 662-8700