Simultaneously Decreasing the Bandgap and Voc Loss in Efficient Ternary Organic Solar Cells. Issue 20 (10th April 2022)

• Record Type: Journal Article
• Authors: Yan, Yangjun; Zhang, Yajie; Liu, Yanan; Shi, Yanan; Qiu, Dingding; Deng, Dan; Zhang, Jianqi; Wang, Boxin; Adil, Muhammad Abdullah; Amin, Kamran; Memon, Waqar Ali; Wang, Mengni; Zhou, Huiqiong; Zhang, Xinghua; Wei, Zhixiang
• Is Part Of: Advanced energy materials. Volume 12:Issue 20(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-04-10
• Subjects: bandgap decreasing -- miscibility -- organic solar cells -- ternary solar cells -- V oc loss; Energy harvesting -- Materials -- Periodicals; Energy conversion -- Materials -- Periodicals; Energy storage -- Materials -- Periodicals; Photovoltaics -- Periodicals; Fuel cells -- Periodicals; Thermoelectric materials -- Periodicals; 621.31
• DOI: 10.1002/aenm.202200129
• Languages: English
• ISSNs: 1614-6832

Abstract

Abstract: Ternary architecture is a promising strategy to further boost the performance of organic solar cells (OSCs). Reducing the bandgap of the active layer materials not only widens the absorption wavelength range and enhances the short‐circuit current ( Jsc ) of the OSC, but also decreases the open‐circuit voltage ( Voc ) of the device, leading to a trade‐off situation for the optimization of the material system. Herein, a small‐molecule donor BTID‐2F, featuring a narrower bandgap than that of PM6, is introduced into a PM6:Y6 based system. The redshift in external quantum efficiency indicates the narrower bandgap and better aggregation in the ternary blends than those of binary ones. Interestingly, lower energy disorder and energy loss are also attained for the ternary devices, leading to higher Voc . Furthermore, owing to the suppressed recombination and morphological optimization, a simultaneous enhancement in the Jsc and fill factor boosts the power conversion efficiency (PCE) of ternary OSC to 17.9% compared to 16.62% for the binary device. Likewise, replacing the acceptor with the L8‐BO molecule further improves the ternary PCE to 18.52%. This work indicates an emerging approach for fabricating high‐performance ternary OSCs with a decreased bandgap and increased Voc . Abstract : High‐performance ternary organic solar cells with a decreased bandgap and increased open‐circuit voltage are fabricated with the small‐molecule donor BTID‐2F featuring a higher highest occupied molecular orbital energy level than PM6 as the third component in the PM6:Y6 system. Significant improvements in ternary device performance are realized, and an impressive power conversion efficiency of 18.52% is obtained.