Asymmetrically noncovalently fused-ring acceptor for high-efficiency organic solar cells with reduced voltage loss and excellent thermal stability. (August 2020)

• Record Type: Journal Article
• Authors: Guo, Qing; Lin, Ji; Liu, Haiqin; Dong, Xingliang; Guo, Xia; Ye, Long; Ma, Zaifei; Tang, Zheng; Ade, Harald; Zhang, Maojie; Li, Yongfang
• Is Part Of: Nano energy. Volume 74(2020)
• Publication Date: 2020-08
• Subjects: Organic solar cells -- Noncovalently fused rings -- Narrow-bandgap acceptor -- Energy loss -- Thermal stability; Nanoscience -- Periodicals; Nanotechnology -- Periodicals; Nanostructured materials -- Periodicals; Power resources -- Technological innovations -- Periodicals; Nanoscience; Nanostructured materials; Nanotechnology; Power resources -- Technological innovations; Periodicals; 621.042
• DOI: 10.1016/j.nanoen.2020.104861
• Languages: English
• ISSNs: 2211-2855

Abstract

Abstract: Simultaneously broadening the spectral response and reducing the energy loss are challenging tasks in the material design of organic solar cells (OSCs). Herein, a novel asymmetrically noncovalently fused-ring electron acceptor (NFEA) with unilateral alkylthio-substituted thiophene π-bridge, namely IDST-4F, is synthesized. IDST-4F exhibits a broader absorption, higher-lying energy levels, larger dipole moments and suppressed crystallinity than its symmetric counterpart (ID-4F) without the π-bridge. Compared to the devices of PM6:ID-4F, the optimized PM6:IDST-4F-based devices display simultaneously enhanced current density and photovoltage, resulting in an excellent power conversion efficiency (PCE) of 14.3%, which is the highest value among the OSCs based on NFEAs reported in the literature to date. More importantly, the PM6:IDST-4F-based OSCs possess excellent thermal stability with 82% of the initial PCE after thermal treatment at 150 °C for 1200 min. In summary, this study indicates that asymmetrically NFEAs are promising to achieve high efficiency with excellent thermal stability. Graphical abstract: Image 1 Highlights: A novel acceptor IDST-4F, consisting of an asymmetric fused-ring core locked by a noncovalent interaction is developed. The PM6:IDST-4F-based OSCs display a significantly improved efficiency of 14.3%. The PM6:IDST-4F-based PSCs exhibit lower energy loss of 0.59 eV and excellent thermal stability.