Affiliation:
1. State Key Laboratory of Polymer Physics and Chemistry Beijing National Laboratory for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences 100190 Beijing China
2. School of Chemistry and Biology Engineering University of Science and Technology Beijing 100083 Beijing China
3. University of Chinese Academy of Sciences 100049 Beijing China
4. School of Physics State Key Laboratory of Crystal Materials Shandong University 250100 Jinan Shandong China
Abstract
AbstractOrganic solar cells (OSCs) are still suffering from the low light utilization and unstable under ultraviolet irradiation. To tackle these challenges, we design and synthesize a non‐fused acceptor based on 1‐(2‐butyloctyl)‐1H‐pyrrole as π‐bridge unit, denoted as GS70, which serves as active layer in the front‐cell for constructing tandem OSCs with a parallel configuration. Benefiting from the well‐complementary absorption spectra with the rear‐cell, GS70‐based parallel tandem OSCs exhibit an improved photoelectron response over the range between 600–700 nm, yielding a high short‐circuit current density of 28.4 mA cm−2. The improvement in light utilization translates to a power conversion efficiency of 19.4 %, the highest value among all parallel tandem OSCs. Notably, owing to the intrinsic stability of GS70, the manufactured parallel tandem OSCs retain 84.9 % of their initial PCE after continuous illumination for 1000 hours. Overall, this work offers novel insight into the molecular design of low‐cost and stability non‐fused acceptors, emphasizing the importance of adopting a parallel tandem configuration for achieving efficient light harvesting and improved photostability in OSCs.
Funder
National Natural Science Foundation of China
Beijing National Laboratory for Molecular Sciences
China Postdoctoral Science Foundation