Organic solar cells (OSCs) with a fused-ring dye, ITIC, and fullerene derivative PC₇₁BM as the acceptor materials were fabricated. Compared to PC₇₁BM-based cells, which reach a power conversion efficiency of 6.91%, the ITIC device shows a significantly higher power conversion efficiency (9.20%). The broader absorption range of ITIC helps to improve the short-circuit current density, which leads to better device efficiency. Electrical characterization, including electrical simulations and impedance analysis, was performed to investigate the physical processes in these OSCs. The results suggest that the charge-recombination loss in the non-fullerene device is even higher than that in PC₇₁BM cells. Morphological analysis reveals that a poor phase-separation in the photoactive layer is responsible for the large recombination loss. Our results indicate that fused-ring acceptor materials are promising candidates for high-efficiency OSCs. Furthermore, if recombination loss could be suppressed effectively, the energy conversion efficiency of non-fullerene organic solar cells can be even higher.

中文翻译：

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尽管电荷复合更高，但非富勒烯有机太阳能电池的光电流和效率有所提高†

制备了具有稠环染料ITIC和富勒烯衍生物PC ₇₁ BM作为受体材料的有机太阳能电池（OSC）。与功率转换效率达到6.91％的PC ₇₁ BM型电池相比，ITIC器件显示出明显更高的功率转换效率（9.20％）。ITIC的吸收范围较宽，有助于改善短路电流密度，从而提高了器件效率。进行了电气表征，包括电气仿真和阻抗分析，以研究这些OSC中的物理过程。结果表明，非富勒烯器件中的电荷复合损失甚至高于PC ₇₁中的电荷复合损失。BM细胞。形态分析表明，光敏层中不良的相分离是造成大量重组损失的原因。我们的结果表明，稠环受体材料是高效OSC的有希望的候选者。此外，如果可以有效地抑制复合损失，则非富勒烯有机太阳能电池的能量转换效率可以更高。