“Head Surgery” of Polycyclic o-Quinones with Cyanated Aromatic Rings towards High Electron Mobility Acceptors Enable 19.6% Additive-Free Binary Organic Solar Cells

Abstract

The development of high-performance organic electron acceptors is pivotal for advancing organic optoelectronic devices. In this paper, a new synthetic approach was developed to construct fused-ring aromatic backbones and the corresponding electron acceptors, namely CD-1 and CD-2, through an o-quinone-mediated cycloaromatization strategy. Both CD-1 and CD-2 exhibit compact 3D interpenetrating network structure with high packing coefficient in single crystal. Consequently, newly designed acceptors demonstrate remarkable electron transport capability as evidenced by the high electron mobility over 1.1 cm2·V−1·s−1 of CD-2 based organic field-effect transistor devices. Notably, the additive-free binary organic photovoltaic devices incorporating CD-1 exhibit power conversion efficiencies (PCEs) of 19.6% with well-balanced open-circuit voltage and short-circuit current density, and the corresponding additive-free binary devices based on CD-2 achieves a decent PCE of 19.1% as well. These results not only underline the potential of new molecular design strategy in providing a robust platform for developing high-performance electron acceptors, but also offer valuable insights into the new design guidelines for achieving high efficiency in organic optoelectronic devices.