Linker Unit Modulation of Polymer Acceptors Enables Highly Efficient Air‐Processed All‐Polymer Solar Cells

Abstract

A group of regioregular polymer acceptors is synthesized by polymerizing Y6 moieties with different linker units including thiophene, vinylene, 2,2'-bithiophene, and thieno[3,2-b]thiophene, and their optoelectrical properties and photovoltaic performances are studied systematically. It is found that the linker units have significant impacts on the backbone planarity, conjugation, and hence optoelectrical properties of polymer acceptors. The vinylene-based PYF-V-o polymer shows a smaller dihedral angle between the end groups and vinylene units and a more rigid polymer backbone, thus affording bathochromic absorption and better electron-transporting capacity. As a result, the PM6:PYF-V-o based all-polymer solar cells (all-PSCs) are able to achieve the highest power conversion efficiency of 16.4% with an unprecedented small voltage loss of 0.49 V. Moreover, the PM6:PYF-V-o blend exhibits good resistance to environmental stressors and the air-processed PM6:PYF-V-o cells can still maintain a high efficiency of 16.1%, which is the best air-processed all-PSC efficiency reported to date. This study provides the structural-property guidance that can be used to facilitate the development of polymer acceptors for all-PSCs.

Improved photovoltaic performance and robustness of all-polymer solar cells enabled by a polyfullerene guest acceptor

“…1a . The polymer acceptor PY-V- γ was synthesized according to our previous works 30 , 47 . PCBM is chosen as another guest component for comparison.…”

Synergistic effect of benzoselenadiazole core and alkoxy side chain substitution on the photovoltaic performance of non-fullerene acceptors

“…The Y6–Se-based device displayed a higher J SC than the Y6–Se–O, mainly due to the stronger ICT effect and extended photon response to 1000 nm. 42…”

Role of Charge‐Carrier Dynamics Toward the Fabrication of Efficient Air‐Processed Organic Solar Cells

“…[104] Kim et al fabricated allpolymer OSCs in air and also reported a record PCE of 16.1% as compared to the control 16.4% PCE for GB-processed all-polymer OSCs. [112] Zhang et al also reported efficient AP-OSCs fabricated via graded-BHJ approach. G-BHJ approach differs from BHJ approach (in which donor and acceptor photoactive materials are dissolved in one solution followed by coating of blend film from the same solution) in a way that the first layer is coated consisting of the single pristine materials (PM6 in this case), followed by coating of the second material (BTP-eC9 NFA in this study) over the rotating substrate.…”