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At present, state-of-the-art single-junction organic photovoltaic devices have power conversion efficiencies of> 9% and> 8% for polymer-and small-molecule-based devices, respectively. Here, we report a solution-processed organic photovoltaic device based on DRCN7T, which employs an oligothiophene-like small molecule with seven conjugation units as the backbone and 2-(1, 1-dicyanomethylene) rhodanine as the terminal unit. With [6, 6]-phenyl C 71-butyric acid methyl ester (PC 71 BM) as the acceptor, an optimized power conversion efficiency of 9.30%(certified at 8.995%) is achieved. The DRCN7T-based devices have a nearly 100% internal quantum efficiency, which we believe is due to an optimized nanoscale interpenetrating donor/acceptor network (with highly crystalline donor fibrils with diameters of∼ 10 nm, close to the exciton diffusion length in organic materials) and the use of an efficient electron …