https://scholar.dgist.ac.kr/handle/20.500.11750/59211 2026-04-06T04:48:05Z 2026-04-06T04:48:05Z Li, Min Chen, Guo Lan, Ai Chung, Sein Que, Mingming Cho, Yongjoon Huang, Bin https://scholar.dgist.ac.kr/handle/20.500.11750/60043 2026-02-10T18:01:24Z 2025-11-30T15:00:00Z

Title: Constructing High-Performance Solar Cells by Incorporating an A1-A2-Type Polymer Donor as a Guest Material Author(s): Li, Min; Chen, Guo; Lan, Ai; Chung, Sein; Que, Mingming; Cho, Yongjoon; Huang, Bin Abstract: Owing to the intramolecular push-pull electron effect between the electron donor (D) unit and electron acceptor (A) unit, the D-A type based polymer donors display outstanding device performance. However, the imperfect energy levels lead to the D-A-type-based polymer device exhibiting high voltage loss. In this study, an A1-A2-type copolymer M1 was developed with 1,3-bis(2-ethylhexyl)-5,7-di(thiophen-2-yl)benzo[1,2-c:4,5-c']dithiophene-4,8-dione (BDD) as the A1 unit and dithieno[3 ',2 ':3,4;2 '',3 '':5,6]benzo[1,2-c][1,2,5]thiadiazole (DTBT) as the A2 unit. Compared with D-A-type-based polymer donor PM6, the A1-A2 type based M1 possesses lower energy levels, broader absorption, and stronger crystallinity. After introducing M1 to the PM6:L8-BO-based system as the guest material, the ternary blend films exhibited exceptional face-on molecular orientation and favorable active-layer morphology, which promotes exciton dissociation and suppresses charge recombination. Consequently, the PM6:M1(5%):L8-BO-based ternary device exhibited an impressive power conversion efficiency (PCE) of 19.70% with simultaneously enhanced photostability, which is superior to the PM6:L8-BO-based binary system. Our work offers an efficient approach to developing high-performance ternary devices by introducing a novel A1-A2 type polymer donors as the guest material.

2025-11-30T15:00:00Z Zhao, Zhenmin Chung, Sein Zhong, Jiancheng Yu, Xuemeng Bai, Liang Tan, Lixing Pang, Wei Zhang, Jingrong Wei, Wuning Chen, Guanlin Li, Xin Azeez, Abdul Huang, Yexiao Cho, Yongjoon Wang, Mingcong Cho, Kilwon Kan, Zhipeng Karuthedath, Safakath https://scholar.dgist.ac.kr/handle/20.500.11750/60042 2026-03-03T05:40:12Z

Title: Tailoring Molecular Orientation with a Polymer Additive Enables Bilayer Organic Solar Cells with 20.2% Efficiency Author(s): Zhao, Zhenmin; Chung, Sein; Zhong, Jiancheng; Yu, Xuemeng; Bai, Liang; Tan, Lixing; Pang, Wei; Zhang, Jingrong; Wei, Wuning; Chen, Guanlin; Li, Xin; Azeez, Abdul; Huang, Yexiao; Cho, Yongjoon; Wang, Mingcong; Cho, Kilwon; Kan, Zhipeng; Karuthedath, Safakath Abstract: Tuning the molecular packing from the edge-on to the preferred face-on orientation is beneficial for improving vertical charge transport and the photovoltaic performance in organic solar cells. However, achieving precise control over this structural transition remains a significant challenge due to the complex processing conditions. Herein, a trace amount of the polymer donor PTO2 as an additive, effectively inducing a preferential face-on molecular orientation in the acceptor phase is incorporated. This strategy enhanced exciton dissociation efficiency, improved charge carrier extraction, reduced trap density, and subsequently achieved a fill factor (FF) nearing 80%, results in a power conversion efficiency (PCE) of 20.2%, the highest reported for bilayer OSCs. Remarkably, the PTO2-driven molecular orientation strategy maintains consistent efficacy across diverse donor-acceptor systems, highlighting its broad applicability. This approach offers a comprehensive insight for the effective modulation of NFA molecular orientation, paving a practical approach for high-performance bilayer OSCs.