16% efficiency all-polymer organic solar cells enabled by a finely tuned morphology via the design of ternary blend

By Tao Liu, Tao Yang, Ruijie Ma, Lingling Zhan, Zhenghui Luo, Guangye Zhang, Yuan Li, Ke Gao, Yiqun Xiao, Jianwei Yu and 21 more. 2021

209 citations recorded by the source corpus.

Summary There is an urgent demand for all-polymer organic solar cells (AP-OSCs) to gain higher efficiency. Here, we successfully improve the performance to 16.09% by introducing a small amount of BN-T, a B←N-type polymer acceptor, into the PM6:PY-IT blend. It has been found that BN-T makes the active layer, based on the PM6:PY-IT:BN-T ternary blend, more crystalline but meanwhile slightly reduces the phase separation, leading to enhancement of both exciton harvesting and charge transport. From a thermodynamic viewpoint, BN-T prefers to reside between PM6 and PY-IT, and the fraction of this fine-tunes the morphology. Besides, a significantly reduced nonradiative energy loss occurs in the ternary blend, along with the coexistence of energy and charge transfer between the two acceptors. The progressive performance facilitated by these improved properties demonstrates that AP-OSCs can possibly comparably efficient with those based on small molecule acceptors, further enhancing the competitiveness of this device type.

Subfields: Electrical and Electronic Engineering, Polymers and Plastics

View Paper: https://www.semanticscholar.org/paper/2453cc06848468666119cb07df4c5a601516a2c9