Chlorination Enabling a Low-Cost Benzodithiophene-Based Wide-Bandgap Donor Polymer with an Efficiency of over 17%

作者：Wang, Hang; Lu, Hao; Chen, Ya-Nan; Ran, Guangliu; Zhang, Andong; Li, Dawei; Yu, Na; Zhang, Zhe; Liu, Yahui^*; Xu, Xinjun^*; Zhang, Wenkai; Bao, Qinye; Tang, Zheng; Bo, Zhishan^*

来源：Advanced Materials, 2022, 34(4): 2105483.

DOI：10.1002/adma.202105483

• charge mobility
• molecular stacking
• organic solar cells
• polymer donor materials
• wide-bandgap donor polymers

Three regioregular benzodithiophene-based donor-donor (D-D)-type polymers (PBDTT, PBDTT1Cl, and PBDTT2Cl) are designed, synthesized, and used as donor materials in organic solar cells (OSCs). Because of the weak intramolecular charge-transfer effect, these polymers exhibit large optical bandgaps (>2.0 eV). Among these three polymers, PBDTT1Cl exhibits more ordered and closer molecular stacking, and its devices demonstrate higher and more balanced charge mobilities and a longer charge-separated state lifetime. As a result of these comprehensive benefits, PBDTT1Cl-based OSCs give a very impressive power conversion efficiency (PCE) of 17.10% with a low nonradiative energy loss (0.19 eV). Moreover, PBDTT1Cl also possesses a low figure-of-merit value and good universality to match with different acceptors. This work provides a simply and efficient strategy to design low-cost high-performance polymer donor materials.

• 单位
  青岛大学