Charge extraction rate in solar cells made of blends of electron donating/accepting organic semiconductors is typically slow due to their low charge carrier mobility. This sets a limit on the active layer thickness and has hindered the industrialization of organic solar cells (OSCs). Herein, charge transport and recombination properties of an efficient polymer (NT812):fullerene blend are investigated. This system delivers power conversion efficiency of >9% even when the junction thickness is as large as 800 nm. Experimental results indicate that this material system exhibits exceptionally low bimolecular recombination constant, 800 times smaller than the diffusion‐controlled electron and hole encounter rate. Comparing theoretical results based on a recently introduced modified Shockley model for fill factor, and experiments, clarifies that charge collection is nearly ideal in these solar cells even when the thickness is several hundreds of nanometer. This is the first realization of high‐efficiency Shockley‐type organic solar cells with junction thicknesses suitable for scaling up.

中文翻译：

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肖克利型聚合物：富勒烯太阳能电池

由于给电子/接受有机半导体的混合物制成的太阳能电池的电荷载流子迁移率低，因此其电荷提取速率通常较慢。这限制了有源层的厚度，并阻碍了有机太阳能电池（OSC）的工业化。本文中，研究了有效聚合物（NT812）：富勒烯共混物的电荷输运和复合性能。即使结厚度达到800 nm，该系统仍能提供大于9％的功率转换效率。实验结果表明，该材料系统表现出异常低的双分子复合常数，比扩散控制的电子和空穴遇到率小800倍。比较基于最近引入的修改后的Shockley模型（用于填充因子）的理论结果和实验结果，阐明了即使厚度为几百纳米，电荷收集在这些太阳能电池中也几乎是理想的。这是具有结点厚度适合按比例放大的高效Shockley型有机太阳能电池的首次实现。