Quadrupole Solid Additive Engineering-Induced Interactions with Both a Donor and an Acceptor Enable Organic Solar...

Area of Science:

• Materials Science
• Organic Electronics
• Photovoltaics

Background:

• Organic solar cell (OSC) performance is critically dependent on active layer morphology, influencing exciton dissociation and charge transport.
• Solid additives are key for tuning molecular packing and blend morphology in OSCs, but research on quadrupolar additives is limited.
• Understanding the influence of quadrupole moments on morphology and device performance is crucial for advancing OSC technology.

Purpose of the Study:

• To design and synthesize a quadrupolar solid additive, 2,5-di(thiophen-2-yl)pyrazine (M3), to investigate its impact on OSC performance.
• To elucidate the mechanisms by which quadrupolar moments influence active layer morphology and charge transfer processes.
• To explore the potential of quadrupolar solid additive engineering for optimizing OSC morphology and device efficiency.

Main Methods:

• Synthesis of the quadrupolar solid additive M3 with a planar configuration and significant quadrupole moment (Qzz = -108.35 D).
• Incorporation of M3 into organic solar cell active layers (PM6:BTP-eC9 and PM6:BTP-eC9:L8-BO).
• Analysis of M3's effect on molecular aggregation, packing, crystallization behavior, nanoscale morphology, and charge transfer.

Main Results:

• M3 effectively modulated molecular aggregation and packing, optimizing nanoscale morphology and facilitating charge transfer.
• M3-treated PM6:BTP-eC9 devices achieved a power conversion efficiency (PCE) of 19.16%.
• PM6:BTP-eC9:L8-BO devices processed with M3 demonstrated an outstanding PCE of 19.62%.

Conclusions:

• Quadrupolar solid additives, exemplified by M3, offer a promising strategy for enhancing OSC performance.
• M3's significant quadrupole moment promotes intermolecular interactions, leading to improved morphology and charge transport.
• This work provides valuable insights into designing quadrupolar additives for optimizing OSC morphology and device efficiency.