Three narrow band gap (NBG) acceptors, namely, TTDTC-0F, TTDTC-2F, and TTDTC-4F, were synthesized by introducing a strong electron-donating unit as the central core. The enhanced intramolecular charge transfer endows the three acceptors with high-lying highest occupied molecular orbitals (HOMOs) of ∼−5.20 eV and ultranarrow band gaps (∼1.25 eV). When blended with poly(3-hexylthiophene) (P3HT), all organic solar cells (OSCs) exhibited a broad photoresponse from 300 to ∼1000 nm. Among them, P3HT:TTDTC-4F-based devices achieved the highest efficiency of 7.81% with a prominent J_sc exceeding 22 mA·cm^–2. This study demonstrates that the conjugated molecules with high HOMOs can also function as acceptor materials for P3HT-based OSCs, which opens a window to increase PCEs of P3HT-based OSCs in the future to the level of the devices based on the current state-of-the-art polymer donor materials.

中文翻译：

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具有高 HOMO 能级的窄带隙非富勒烯受体实现具有 1000 nm 光响应的基于 P3HT 的有机太阳能电池

通过引入强电子给体单元作为中心核，合成了三种窄带隙 (NBG) 受体，即TTDTC-0F、TTDTC-2F和TTDTC-4F。增强的分子内电荷转移使三个受体具有~-5.20 eV的高位最高占据分子轨道（HOMO）和超窄带隙（~1.25 eV）。当与聚（3-己基噻吩）（P3HT）混合时，所有有机太阳能电池（OSC）都表现出从 300 到 1000 nm 的广泛光响应。其中，基于P3HT: TTDTC-4F的器件实现了 7.81% 的最高效率，突出的J _sc超过了 22 mA·cm ^–2. 该研究表明，具有高 HOMO 的共轭分子也可以作为基于 P3HT 的 OSCs 的受体材料，这打开了一个窗口，可以在未来将基于 P3HT 的 OSCs 的 PCE 提高到基于当前状态的器件水平。 -最先进的聚合物供体材料。