High-efficiency flexible organic solar cells with a polymer-incorporated pseudo-planar heterojunction
Lin Zhang,
Yuxin He,
Wen Deng,
Xueliang Guo,
Zhaozhao Bi,
Jie Zeng,
Hui Huang,
Guangye Zhang,
Chen Xie,
Yong Zhang,
Xiaotian Hu,
Wei Ma,
Yongbo Yuan,
Xiaoming Yuan
Affiliations
Lin Zhang
Hunan Key Laboratory for Super Microstructure and Ultrafast Process, School of Physics, Central South University
Yuxin He
Hunan Key Laboratory for Super Microstructure and Ultrafast Process, School of Physics, Central South University
Wen Deng
Hunan Key Laboratory for Super Microstructure and Ultrafast Process, School of Physics, Central South University
Xueliang Guo
Hunan Key Laboratory for Super Microstructure and Ultrafast Process, School of Physics, Central South University
Zhaozhao Bi
State Key Laboratory for Mechanical Behavior of Materials, Xi’an Jiaotong University
Jie Zeng
Department of Materials Science and Engineering, and Shenzhen Engineering Research and Development Center for Flexible Solar Cells, Southern University of Science and Technology
Hui Huang
College of New Materials and New Energies, Shenzhen Technology University
Guangye Zhang
College of New Materials and New Energies, Shenzhen Technology University
Chen Xie
College of New Materials and New Energies, Shenzhen Technology University
Yong Zhang
Department of Materials Science and Engineering, and Shenzhen Engineering Research and Development Center for Flexible Solar Cells, Southern University of Science and Technology
Xiaotian Hu
Institute of Polymers and Energy Chemistry, College of Chemistry and Chemical Engineering, Nanchang University
Wei Ma
State Key Laboratory for Mechanical Behavior of Materials, Xi’an Jiaotong University
Yongbo Yuan
Hunan Key Laboratory for Super Microstructure and Ultrafast Process, School of Physics, Central South University
Xiaoming Yuan
Hunan Key Laboratory for Super Microstructure and Ultrafast Process, School of Physics, Central South University
Abstract Organic solar cells (OSCs) are considered as a crucial energy source for flexible and wearable electronics. Pseudo-planar heterojunction (PPHJ) OSCs simplify the solution preparation and morphology control. However, non-halogenated solvent-printed PPHJ often have an undesirable vertical component distribution and insufficient donor/acceptor interfaces. Additionally, the inherent brittleness of non-fullerene small molecule acceptors (NFSMAs) in PPHJ leads to poor flexibility, and the NFSMAs solution shows inadequate viscosity during the printing of acceptor layer. Herein, we propose a novel approach termed polymer-incorporated pseudo-planar heterojunction (PiPPHJ), wherein a small amount of polymer donor is introduced into the NFSMAs layer. Our findings demonstrate that the incorporation of polymer increases the viscosity of acceptor solution, thereby improving the blade-coating processability and overall film quality. Simultaneously, this strategy effectively modulates the vertical component distribution, resulting in more donor/acceptor interfaces and an improved power conversion efficiency of 17.26%. Furthermore, PiPPHJ-based films exhibit superior tensile properties, with a crack onset strain of 12.0%, surpassing PPHJ-based films (9.6%). Consequently, large-area (1 cm2) flexible devices achieve a considerable efficiency of 13.30% and maintain excellent mechanical flexibility with 82% of the initial efficiency after 1000 bending cycles. These findings underscore the significant potential of PiPPHJ-based OSCs in flexible and wearable electronics.
