Balanced Partnership between Donor and Acceptor Components in Nonfullerene Organic Solar Cells with >12% Efficiency
Abstract
Relative to electron donors for bulk heterojunction organic solar cells (OSCs), electron acceptors that absorb strongly in the visible and even near‐infrared region are less well developed, which hinders the further development of OSCs. Fullerenes as traditional electron acceptors have relatively weak visible absorption and limited electronic tunability, which constrains the optical and electronic properties required of the donor. Here, high‐performance fullerene‐free OSCs based on a combination of a medium‐bandgap polymer donor (FTAZ) and a narrow‐bandgap nonfullerene acceptor (IDIC), which exhibit complementary absorption, matched energy levels, and blend with pure phases on the exciton diffusion length scale, are reported. The single‐junction OSCs based on the FTAZ:IDIC blend exhibit power conversion efficiencies up to 12.5% with a certified value of 12.14%. Transient absorption spectroscopy reveals that exciting either the donor or the acceptor component efficiently generates mobile charges, which do not suffer from recombination to triplet states. Balancing photocurrent generation between the donor and nonfullerene acceptor removes undesirable constraints on the donor imposed by fullerene derivatives, opening a new avenue toward even higher efficiency for OSCs.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Mar 07, 2018
- Source ID
- 10.1002/adma.201706363
Entities
People
- Chunru Wang
- Feng Gao
- Fuwen Zhao
- Jian‐xin Tang
- Jing‐de Chen
- Justin Hodgkiss
- Kai Chen
- Qianqian Zhang
- Shyamal K. K. Prasad
- Wanzhu Cai
- Wei Ma
- Wei You
- Xiaowei Zhan
- Yang Wu
- Yuze Lin
Organizations
- Institute of Chemistry
- Knut and Alice Wallenberg Foundation
- Linköping University
- Ministry of Science and Technology of the People's Republic of China
- National Natural Science Foundation of China
- National Science Foundation
- Office of Naval Research
- Peking University
- Soochow University
- United States Department of Energy
- University of North Carolina at Chapel Hill
- Victoria University of Wellington
- Xi'an Jiaotong University