Three fused-ring electron acceptors (SIDIC, DIDIC and TIDIC) were designed and synthesized using single bond, vinylene and acetylene units linked indaceno[3,2-b]dithiophene dimers as electron-rich cores and 3-(1,1-dicyanomethylene)-5,6-difluoro-1-indanone as electron-deficient termini. These molecules exhibit strong absorption from 550 to 900 nm with large attenuation coefficients of 1.8–2.0 × 10⁵ M⁻¹ cm⁻¹ and high electron mobilities of 2.2–4.9 × 10⁻³ cm² V⁻¹ s⁻¹. In combination with wide-bandgap polymer FTAZ as a donor, organic solar cells exhibit efficiencies of 9.3–13.1%. Effects of the linking units on optical, electronic, morphologic, and photovoltaic properties were revealed. Relative to SIDIC, vinylene-bridged DIDIC shows red-shifted absorption, while acetylene-bridged TIDIC shows blue-shifted absorption. Compared with SIDIC and DIDIC, TIDIC has a lower HOMO, higher electron mobility, and higher device efficiency.

中文翻译：

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连接单元对稠环电子受体二聚体的影响

设计并合成了三个稠环电子受体（SIDIC，DIDIC和TIDIC），它们以单键，亚乙烯基和乙炔单元连接的茚并[3,2- b ]二噻吩二聚体为富电子核和3-（1,1-二氰基亚甲基）合成。 ）-5,6-二氟-1-茚满酮作为电子不足的末端。这些分子在550至900 nm处表现出强吸收性，衰减系数为1.8–2.0×10 ⁵ M ^-1 cm ^-1，电子迁移率高，为2.2–4.9×10 ^-3 cm ² V ^-1 s ^-1。与宽带隙聚合物FTAZ结合作为供体，有机太阳能电池的效率为9.3-13.1％。揭示了连接单元对光学，电子，形态和光伏性质的影响。相对于SIDIC，亚乙烯基桥联的DIDIC显示红移吸收，而乙炔桥联的TIDIC显示蓝移吸收。与SIDIC和DIDIC相比，TIDIC具有更低的HOMO，更高的电子迁移率和更高的器件效率。