Improved photovoltaic performance and robustness of all-polymer solar cells enabled by a polyfullerene guest acceptor

Abstract

Fullerene acceptors typically possess excellent electron-transporting properties and can work as guest components in ternary organic solar cells to enhance the charge extraction and efficiencies. However, conventional fullerene small molecules typically suffer from undesirable segregation and dimerization, thus limiting their applications in organic solar cells. Herein we report the use of a poly(fullerene-alt-xylene) acceptor (PFBO-C12) as guest component enables a significant efficiency increase from 16.9% for binary cells to 18.0% for ternary all-polymer solar cells. Ultrafast optic and optoelectronic studies unveil that PFBO-C12 can facilitate hole transfer and suppress charge recombination. Morphological investigations show that the ternary blends maintain a favorable morphology with high crystallinity and smaller domain size. Meanwhile, the introduction of PFBO-C12 reduces voltage loss and enables all-polymer solar cells with excellent light stability and mechanical durability in flexible devices. This work demonstrates that introducing polyfullerenes as guest components is an effective approach to achieving highly efficient ternary all-polymer solar cells with good stability and mechanical robustness.

High Miscibility‐Induced Reduction of Trap Density in All‐Polymer Solar Cells Using Hybrid Cyclohexyl‐Hexyl Side Chains

“…Taking advantage of mechanical stretchability of all polymer blend films, [68,69] flexible devices were also fabricated with architecture of AgNW/PEDOT: PSS/active layer/PDINN/Ag (Figure 5a). The current J-V curves under optimized condition and corresponding photovoltaic parameters are presented in Figure 5d and Table S4, Supporting Information.…”

PY‐IT, an Excellent Polymer Acceptor†

“…These works further strengthen the effectiveness of developing polyfullerene guests into ternary systems for achieving highly efficient, stable, and mechanical robustness ternary all‐PSCs. [ 111 ] These studies highlight the significance of ternary strategies in achieving efficient all‐PSCs by improving phase separation, optimizing morphology, facilitating charge transfer, and enhancing overall device performance.…”

Sequence-Defined Conjugated Oligomers in Donor–Acceptor Dyads

“…Conjugated polymers form the basis of numerous aspects of chemical and materials research including, but not limited to, organic electronic devices, − energy storage, − fluorescent biosensors and therapeutics, − and visible-light-driven photocatalysis. , The intense interest in these materials is due, in part, to their large degree of broadly tunable electronic and physical properties. While these properties are typically dictated by the identity of the initial monomer, they may also be influenced by the chain length, monomer sequence, and side chain composition. − However, the inherent disperse nature of polymers often prevents the development of clear structure–property relationships that are needed to further elucidate fundamental processes and advance the application of these materials.…”