Hu, D., Tang, H., Karuthedath, S., Chen, Q., Chen, S., Khan, J. I., Liu, H., Yang, Q., Gorenflot, J., Petoukhoff, C. E., Duan, T., Lu, X., Laquai, F., Lu, S.,
Adv. Funct. Mater. 2022, 2211873.
doi.org/10.1002/adfm.202211873
Abstract
The commercial viability of all-small-molecule (ASM) organic solar cells (OSCs) requires high efficiency, long-term stability, and low-cost production.
However, satisfying all these factors at the same time remains highly challenging. Herein, a volatile solid additive, namely, 1,8-dichloronaphthalene (DCN) is demonstrated to simultaneously enhance the power conversion efficiency (PCE) and the storage, thermal as well as photo stabilities of oligothiophene ASM-OSCs with concise and low-cost syntheses.
The improved PCEs are mainly due to the DCN-induced morphology control with improved exciton dissociation and reduced non-geminate recombination. Notably, the PCE of 16.0% stands as the best value for oligothiophene ASM-OSCs and is among the top values for all types of binary ASM-OSCs. In addition, devices incorporating DCN have shown remarkable long-term stability, retaining over 90% of their initial PCE after dark storage aging of 3000 h and thermal or light stressing of 500 h.
The findings demonstrate that the volatile-solid-additive strategy can be a simple yet effective method of delivering highly efficient and stable oligothiophene ASM-OSCs with excellent commercial viability.
The 1D numerical drift-diffusion module of Setfos was used to simulate the O-ASM-OSCs device J–V characteristics.