Double-cable conjugated polymers contain electron-donating (D) backbones and electron-accepting (A) side units, in which the nanophase separation of the donor and acceptor segments is a crucial factor to determine the photovoltaic performance of single-component organic solar cells (SCOSCs). In this work, three random double-cable conjugated polymers (denoted as P1–P3 with enhanced acceptor contents) have been designed to tailor the nanophase separation of D/A to realize high-performance SCOSCs. These new random double-cable conjugated polymers contain identical polymer backbones with varied contents of near-infrared acceptor side units. It is observed that the acceptor contents could effectively tune the aggregation degree of the backbone and acceptor (shown in the absorption spectra and grazing-incidence wide-angle X-ray scattering measurement) and further influence the construction of charge-transporting pathways. Therefore, a moderate content of acceptor side units provides balanced D/A aggregation and optimal nanophase separation, resulting in a high efficiency of 9.4% in SCOSCs. These results demonstrate that random double-cable conjugated polymers are an excellent model for studying the impact of their aggregation/crystallinity so as to realize high-performance SCOSCs.
KAUST Repository Item: Exported on 2023-06-14
Acknowledgements: This study was jointly supported by MOST (2018YFA0208504), the Beijing Natural Science Foundation (JQ21006) and NSFC (92163128, 52073016, 52163018, and 21905018) of China. This work was further supported by the Fundamental Research Funds for the Central Universities (buctrc201828, XK1802-2), and the Opening Foundation of State Key Laboratory of Organic-Inorganic Composites of Beijing University of Chemical Technology (oic-202201006). This work was performed in part at the SAXS/WAXS beamline at the Australian Synchrotron, part of ANSTO. The research reported in this publication was supported by funding from the King Abdullah University of Science and Technology (KAUST).