Tetrafluoroquinoxaline based polymers for non-fullerene polymer solar cells with efficiency over 9%. (December 2016)

• Record Type: Journal Article
• Authors: Yuan, Jun; Qiu, Lixia; Zhang, Zhi-Guo; Li, Yongfang; Chen, Yiwang; Zou, Yingping
• Is Part Of: Nano energy. Volume 30(2016:Dec.)
• Page Start: 312
• Page End: 320
• Publication Date: 2016-12
• Subjects: Non-fullerene polymer solar cells -- Tetrafluoroquinoxaline -- Non-fullerene small molecule -- Light harvesting -- Photovoltaic properties; 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.2016.10.008
• Languages: English
• ISSNs: 2211-2855

Abstract

Abstract: In order to increase the power conversion efficiency (PCE) of non -fullerene polymer solar cells (PSCs), the absorption spectra of donor and acceptor should be complementary for efficient light harvesting. Here, we designed and synthesized two types of medium bandgap polymers in which two dimension-conjugated benzodithiophene (BDT) (BDTT and BDTPS) was used as the electron donating units and tetrafluoroquinoxaline ( ff Qx) was used as electron accepting unit, namely P ff Qx-T and P ff Qx-PS, for the application as donor in the PSCs with a popular non-fullerene small molecule ITIC as acceptor. Their optical, electrochemical and photovoltaic properties were well investigated. Under AM 1.5G, 100 mW/cm −2, all the PSCs with the ff Qx-based polymers as donor exhibited PCEs over 8% (8.47% for P ff Qx-T and 9.12% for P ff Qx-PS). To the best of our knowledge, the PCE of 9.12% is the highest value for BDT-Qx fullerene-free PSCs to date, which is even higher than that of fullerene-based devices. Graphical abstract: Using tetrafluoroquinoxaline based polymers as electron donor in non-fullerene polymer solar cells, a power conversion efficiency of 9.12% with a high V oc of 0.97 V was obtained. Highlights: Two types of tetrafluoroquinoxaline ( ff Qx) polymers- P ff Qx-T and P ff Qx-PS, were synthesized. Variation of side chains has minimal effect on LUMO level, but moderate impact on HOMO level. PSCs based on P ff Qx-PS/ITIC exhibits a high PCE of 9.12% with a high V oc of 0.97 V.