Small-Molecule Acceptor with Unsymmetric Substituents and Fused Rings for High-Performance Organic Solar Cells with Enhanced Mobility and Reduced Energy Losses

• Published in: ACS applied materials & interfaces Vol. 14; no. 46; pp. 52058 - 52066
• Main Authors: Li, Zechen, Kong, Xiaolei, Chen, Zeng, Angunawela, Indunil, Zhu, Haiming, Li, Xiaojun, Meng, Lei, Ade, Harald, Li, Yongfang
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 23.11.2022; American Chemical Society (ACS)
• Subjects: Energy, Environmental, and Catalysis Applications; Materials Science; Science & Technology - Other Topics; organic solar cells; small-molecule acceptors; unsymmetric molecular structure; nonradiative energy loss; alkoxy substituent
• ISSN: 1944-8244; 1944-8252
• DOI: 10.1021/acsami.2c17235

A new unsymmetric small-molecule acceptor (SMA) BTPOSe-4F was designed by unsymmetric structure modification to Y6 with an alkyl upper side chain replaced by an alkoxy side chain and a sulfur atom in its central fused ring replaced by a selenium atom, for the application as an acceptor to fabricate organic solar cells (OSCs). BTPOSe-4F exhibits a higher lowest unoccupied molecular orbital (LUMO) energy level, a reduced nonradiation energy loss, and better charge extraction properties in its binary OSCs with a higher V oc of 0.886. Furthermore, the ternary OSCs with the addition of PC71BM demonstrated a higher power conversion efficiency (PCE) of 17.33% with V oc of 0.890 V. This work reveals that the unsymmetric modification strategy can further give impetus to the photovoltaic performance promotion of OSCs for Y6-series SMAs.