High-Efficiency Quinoxaline-Based Nonfused Ring Electron Acceptors via Precisely Manipulating Noncovalent Interactions

Le résumé fourni par la source

Quinoxaline (Qx) units, as a class of electron-deficient groups, have been widely incorporated into non-fullerene acceptors owing to their strong quinoid character and multiple substitution positions. In this work, three A-D-A′-D-A-type nonfused ring electron acceptors (NFREAs), namely, NAQx-1, NAQx-2, and NAQx-3, were developed using Qx units as the A′ moiety. Due to their distinct substituent groups, NAQx-1, NAQx-2, and NAQx-3 can form S···N, S···O, and S···F noncovalent interactions, respectively, which can restrict the free rotation of C–C single bonds in conjugated backbone. Meanwhile, NAQx-1 possesses a conformation that is more planar than those of NAQx-2 and NAQx-3, endowing the molecule with broad absorption and high electron mobility. The blend film based on PBDB-T: NAQx-1 shows a uniform fibril network morphology, along with superior exciton dissociation and high charge mobility. Consequently, the as-cast PBDB-T: NAQx-1 device achieves a remarkable PCE of 13.46%, outperforming the corresponding devices based on NAQx-2 and NAQx-3 . This study demonstrates the excellent potential of the quinoxaline unit as an electron-deficient building block for efficient NFREAs in OSCs.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.