This paper presents a novel non-monotonic intermediate state manipulation (ISM) strategy for enhancing the efficiency of organic solar cells (OSCs). By employing 1,3,5-trichlorobenzene (TCB) as a crystallization regulator, the researchers optimized the film crystallization process and regulated the self-organization of the bulk-heterojunction (BHJ) in a non-monotonic manner—first enhancing and then relaxing molecular aggregation. This approach successfully reduced non-radiative recombination loss, leading to a record binary organic solar cell efficiency of 19.31% (18.93% certified) with low non-radiative recombination loss of 0.190 eV in PM6:BTP-eC9 OSCs and even lower loss of 0.168 eV in PM1:BTP-eC9 OSCs (19.10% efficiency). The ISM strategy shows promise for improving future OSC technology.

Jiehao Fu, Patrick W. K. Fong, Heng Liu, Chieh-Szu Huang, Xinhui Lu, Shirong Lu, Maged Abdelsamie, Tim Kodalle, Carolin M. Sutter-Fella, Yang Yang, Gang Li