Enhance the performance of organic solar cells by nonfused ring electron acceptors bearing a pendent perylenediimide group

A new nonfused ring electron acceptor PDI-DO-2F is designed and synthesized by attaching perylenediimide (PDI) unit as a pendent group to the central donor core. Compared with the control molecule DO-2F, the introduction of PDI lateral substituent can greatly enhance the solubility and decrease the crystallinity of the resulted acceptor. The PBDB-T:PDI-DO-2F blend film exhibits a much better morphology with higher and more balanced carrier mobility in contrast to PBDB-T:DO-2F one. PDI-DO-2F based organic solar cells (OSCs) give a power conversion efficiency (PCE) of 11.78%, higher than DO-2F based ones (9.82%). Furthermore, PDI-DO-2F based OSCs shows a Delta Enon-rad value of 0.23 eV, which is significantly lower than the DO-2F based ones (0.28 eV). More importantly, the addition of PDI-DO-2F as the third component to the PBDB-T:DO-2F binary system can optimize the morphology of blend films and improve the shelf stability of devices. And the PBDB-T:DO-2F:PDI-DO-2F based ternary OSCs achieve a higher PCE of 13.82%.

Automated summary

A new nonfused ring electron acceptor PDI-DO-2F is designed and synthesized, which can greatly enhance the solubility and decrease the crystallinity compared with the control molecule DO-2F. The PBDB-T:PDI-DO-2F blend film exhibits a better morphology and higher carrier mobility, resulting in a higher power conversion efficiency (PCE) of 11.78% in PDI-DO-2F based organic solar cells (OSCs) compared to DO-2F based ones (9.82%). Furthermore, the addition of PDI-DO-2F as the third component in the PBDB-T:DO-2F binary system improves the morphology of blend films and enhances the shelf stability of devices, contributing to a higher PCE of 13.82% in PBDB-T:DO-2F:PDI-DO-2F based ternary OSCs.