Conformation Locking on Fused‐Ring Electron Acceptor for High‐Performance Nonfullerene Organic Solar Cells
Abstract
In this work, sidechain engineering on conjugated fused‐ring acceptors for conformation locking is demonstrated as an effective molecular design strategy for high‐performance nonfullerene organic solar cells (OSCs). A novel nonfullerene acceptor (ITC6‐IC) is designed and developed by introducing long alkyl chains into the terminal electron‐donating building blocks. ITC6‐IC has achieved definite conformation with a planar structure and better solubility in common organic solvents. The weak electron‐donating hexyl upshifts the lowest unoccupied molecular orbital level of ITC6‐IC, resulting in a higher VOC in comparison to the widely used ITIC. The OSCs based on PBDB‐T:ITC6‐IC reveal a promising power conversion efficiency of 11.61% and an expected high VOC of 0.97 V. The weaker π–π stacking induced by steric hindrance affords ITC6‐IC with enhanced compatibility with polymer donors. The blend film treated with suitable thermal annealing exhibits a fibril crystallization feature with a good bicontinuous network morphology. The results indicate that the molecular design approach of ITC6‐IC can be inspirational for future development of nonfullerene acceptors for high efficiency OSCs.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jan 17, 2018
- Source ID
- 10.1002/adfm.201705095
Entities
People
- Feng Liu
- Fujun Zhang
- Jia Sun
- Jiangsheng Yu
- Jianlong Zhou
- Thomas Paul Russell
- Weihua Tang
- Xinxing Yin
- Yufeng Jiang
- Zhenghao Hu
- Zhuohan Zhang
Organizations
- Beijing Jiaotong University
- Lawrence Berkeley National Laboratory
- Nanjing University of Science and Technology
- National Natural Science Foundation of China
- Office of Naval Research Global
- Shanghai Jiao Tong University