Athanasopoulos Stavros, Tscheuschner Steffen, Bässler Heinz, Köhler Anna
Departamento de Física, Universidad Carlos III de Madrid , Avenida Universidad 30, Leganés 28911, Madrid, Spain.
J Phys Chem Lett. 2017 May 4;8(9):2093-2098. doi: 10.1021/acs.jpclett.7b00595. Epub 2017 Apr 26.
We demonstrate that efficient and nearly field-independent charge separation of electron-hole pairs in organic planar heterojunction solar cells can be described by an incoherent hopping mechanism. Using kinetic Monte Carlo simulations that include the effect of on-chain delocalization as well as entropic contributions, we simulate the dissociation of the charge-transfer state in polymer-fullerene bilayer solar cells. The model further explains experimental results of almost field independent charge separation in bilayers of molecular systems with fullerenes and provides important guidelines at the molecular level for maximizing the efficiencies of organic solar cells. Thus, utilizing coherent phenomena is not necessarily required for highly efficient charge separation in organic solar cells.
我们证明，有机平面异质结太阳能电池中电子 - 空穴对的高效且几乎与电场无关的电荷分离可以用非相干跳跃机制来描述。通过包含链上离域效应以及熵贡献的动力学蒙特卡罗模拟，我们模拟了聚合物 - 富勒烯双层太阳能电池中电荷转移态的解离。该模型进一步解释了含富勒烯分子体系双层中几乎与电场无关的电荷分离的实验结果，并在分子水平上为最大化有机太阳能电池效率提供了重要指导。因此，在有机太阳能电池中实现高效电荷分离不一定需要利用相干现象。
