IRFP: Controlling the Order of Functional Polymers and Their Corresponding Blends

Treat Neil D, Santa Barbara CA

Investigators

Abstract

The International Research Fellowship Program enables U.S. scientists and engineers to conduct nine to twenty-four months of research abroad. The program's awards provide opportunities for joint research, and the use of unique or complementary facilities, expertise and experimental conditions abroad. This award is co-funded by the Office of International Science and Engineering and by the Electronics, Photonics and Magnetic Devices Program in the Electrical, Communications and Cyber Systems Division. This award will support a twelve-month research fellowship by Dr. Neil D. Treat to work with Dr. Natalie Stingelin at Imperial College London in London, United Kingdom. One of society's challenges is to develop a clean, renewable, and sustainable energy source. Organic photovoltaics (OPVs) offer great potential as a low-cost solution to this need because of their ability to be solution processed over large areas. Currently, OPVs are approaching the estimated 10% power conversion efficiency needed to achieve economic viability, but further improvement and large area utilization is predicated on a deeper understanding of how to control their complex microstructure and how this affects the device performance. Thus, gaining control over the blend microstructure is of utmost importance for the continued technological development of OPVs so that they may be realized as a renewable and sustainable energy source. This project is currently developing strategies to control the microstructure of OPVs materials through the addition of additives. This strategy provides a means to control the active layer microstructure, which can be used to further both our fundamental and practical understanding of this system. Specifically, this project is using nucleating agents - additives that control the microstructure of semicrystalline polyolefins - to control the ordering in OPV materials and to correlate this change to their electronic properties. The main goal of this project is to link the changes in the molecular ordering of neat polymer based devices to the electronic performance and understanding how the polymer architecture can influence the efficiency of nucleation and the resulting electronic properties. The second portion involves extending this understanding to develop processing strategies for large area coating. Indeed, the use of nucleating agents is an unexplored, but potentially useful strategy for controlling the microstructure of OPV materials.