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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 × 10 5 M −1 cm −1 and high electron mobilities of 2.2–4.9 × 10 −3 cm 2 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.