Hydrogen bond induced high-performance quaternary organic solar cells with efficiency up to 17.48% and superior thermal stability

Abstract

Multicomponent systems have been widely investigated to expand absorption spectra, ameliorate morphology and achieve high-performance organic solar cells (OSCs). Here, we reveal a novel quaternary OSC based on a PM6:Y6:SR197:PC₇₁BM system with a power conversion efficiency (PCE) of up to 17.48%, one of the highest efficiencies in organic photovoltaics. The N–H bonds of SR197 react with the F atom of acceptor Y6 to form intermolecular hydrogen bonds that regulate the morphology of the blended film and inhibit bimolecular recombination, so that a PCE of 16.83% is achieved for the ternary OSC based on a PM6:Y6:SR197 system. However, the PCE of PM6:Y6:PC₇₁BM-based devices is 16.72% due to the fullerene derivative PC₇₁BM exhibiting strong isotropic transport ability. The quaternary OSC combines the advantages of the above two ternary devices, and it is noteworthy that SR197 can also form hydrogen bonds with PC₇₁BM, which allows targeted morphology control and improved device stability while increasing photon utilization. Therefore, the efficiency of the quaternary device rose by 12% in contrast to the binary device (15.56%). Our results detail the use of a hydrogen bonding strategy to overcome the disadvantages of the difficult-to-control morphology of multiple component devices, which is a valid way to achieve high-performance quaternary OSCs.