Molecular and Macromolecular Organic Acceptors for Photovoltaic Applications

Arizona State University, Scottsdale AZ

Investigators

Abstract

CBET-0756148 Li The Sun is an ultimate source of sustainable energy for the humankind. Engineering creative and cost efficient ways to harness this energy into useful work will tremendously benefit us and decreases (to eliminate) our dependence on fossil fuel in the future. Solar cells can help greatly in this regard. Organic photovoltaics promise a low cost and more robust alternative to most inorganic solar cells due to their facile suitability to high throughput techniques, especially roll-to-roll printing. However, there are several challenges to be solved before a full scale market introduction of organic solar cells can take place. Such challenges include lifetime and efficiency. In this venue, the ASU investigators propose to engineer new materials and optimize their device performance. In this regard, the investigators propose to develop a range of stable oligorylene diimide molecules as well as macromolecular materials for use as electron acceptors in organic solar cells. The macromolecular structures will provide a window to low cost solution-based processing of organic solar cells. The materials will be tuned in order to answer questions such as: a) what thermal property requirement is needed for devices with longer lifetime, b) what dictates, and how to enhance, the electrochemical stability in such materials, c) how to extend the absorption range to harness more of the solar spectrum into useful charges needed for the operation of solar cells, and d) what are the basic materials and device design rules that will assist in increasing the exciton diffusion length. This is a highly interdisciplinary collaboration. Such approach will lead to constant interactions between the synthesis and device groups which will expedite the discovery process. Graduate students will learn how to interact with different teams having different but complimentary backgrounds. Undergraduate students will be introduced to the importance of new materials and device optimization in creating reliable and efficient solar cells. This will also expose them to contemporary topics in research early on in their university career thus enhancing their educational training. The PIs will help to develop educational modules associated with energy for sustainability, entitled Solar Electricity, which trains undergraduate interns to visit more than 70 schools annually and give several hundred presentations to over 20,000 students and teachers. This in turn will enhance their appreciation to science and engineering, thus increasing the chances of recruiting more US nationals to technical areas at the university level.