title: Tandem Solar Cells from Accessible Low Band-Gap Polymers Using an Efficient Interconnecting Layer.
abstract: Tandem solar cell architectures are designed to improve device photoresponse by enabling the capture of wider range of solar spectrum as compared to single-junction device. However, the practical realization of this concept in bulk-heterojunction polymer systems requires the judicious design of a transparent interconnecting layer compatible with both polymers. Moreover, the polymers selected should be readily synthesized at large scale (>1 kg) and high performance. In this work, we demonstrate a novel tandem polymer solar cell that combines low band gap poly isoindigo [P(T3-iI)-2], which is easily synthesized in kilogram quantities, with a novel Cr/MoO3 interconnecting layer. Cr/MoO3 is shown to be greater than 80% transparent above 375 nm and an efficient interconnecting layer for P(T3-iI)-2 and PCDTBT, leading to 6% power conversion efficiencies under AM 1.5G illumination. These results serve to extend the range of interconnecting layer materials for tandem cell fabrication by establishing, for the first time, that a thin, evaporated layer of Cr/MoO3 can work as an effective interconnecting layer in a tandem polymer solar cells made with scalable photoactive materials.
authors.affiliation: Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson Air Force Base , Dayton, Ohio 45433, United States.|Biological and Nanoscale Technologies Division, UES Inc. Dayton, Ohio 45432, United States.
authors.forename: Santanu
authors.initials: S
authors.lastname: Bag
authors.affiliation: Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson Air Force Base , Dayton, Ohio 45433, United States.|Biological and Nanoscale Technologies Division, UES Inc. Dayton, Ohio 45432, United States.
authors.forename: Romesh J
authors.initials: RJ
authors.lastname: Patel
authors.affiliation: Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson Air Force Base , Dayton, Ohio 45433, United States.|Biological and Nanoscale Technologies Division, UES Inc. Dayton, Ohio 45432, United States.
authors.forename: Ajaykumar
authors.initials: A
authors.lastname: Bunha
authors.affiliation: School of Chemistry and Biochemistry, School of Materials Science and Engineering, Center for Organic Photonics and Electronics, Georgia Tech Polymer Network, Georgia Institute of Technology , Atlanta, Georgia 30332, United States.
authors.forename: Caroline
authors.initials: C
authors.lastname: Grand
authors.affiliation: Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson Air Force Base , Dayton, Ohio 45433, United States.
authors.forename: J Daniel
authors.initials: JD
authors.lastname: Berrigan
authors.affiliation: Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson Air Force Base , Dayton, Ohio 45433, United States.
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Dalton
authors.affiliation: Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson Air Force Base , Dayton, Ohio 45433, United States.
authors.forename: Benjamin J
authors.initials: BJ
authors.lastname: Leever
authors.affiliation: School of Chemistry and Biochemistry, School of Materials Science and Engineering, Center for Organic Photonics and Electronics, Georgia Tech Polymer Network, Georgia Institute of Technology , Atlanta, Georgia 30332, United States.
authors.forename: John R
authors.initials: JR
authors.lastname: Reynolds
authors.affiliation: Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson Air Force Base , Dayton, Ohio 45433, United States.
authors.forename: Michael F
authors.initials: MF
authors.lastname: Durstock
keywords: interconnecting layer; isoindigo; polymers; scalable; solution processing; tandem solar cells