Slow light enhanced singlet exciton fission solar cells with a 126% yield of electrons per photon

• Main Authors: Thompson, Nicholas J. (Contributor), Goldberg, David (Author), Menon, Vinod M. (Author), Congreve, Daniel Norbert (Contributor), Baldo, Marc A (Author)
• Other Authors: Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science (Contributor), Massachusetts Institute of Technology. Department of Materials Science and Engineering (Contributor), Massachusetts Institute of Technology. Energy Frontier Research Center for Excitonics (Contributor), Baldo, Marc A. (Contributor)
• Format: Article
• Language: English
• Published: Association for Computing Machinery (ACM), 2014-03-28T15:48:38Z.
• Subjects: Article
• Online Access: Get fulltext

Singlet exciton fission generates two triplet excitons per absorbed photon. It promises to increase the power extracted from sunlight without increasing the number of photovoltaic junctions in a solar cell. We demonstrate solar cells with an external quantum efficiency of 126% by enhancing absorption in thin films of the singlet exciton fission material pentacene. The device structure exploits the long photon dwell time at the band edge of a distributed Bragg reflector to achieve enhancement over a broad range of angles. Measuring the reflected light from the solar cell establishes a lower bound of 137% for the internal quantum efficiency.
United States. Dept. of Energy. Office of Basic Energy Sciences (Award DE-SC0001088)
National Science Foundation (U.S.). Graduate Research Fellowship Program (Grant 1122374)