Abstract In this paper, the effect of mobility and active layer thickness on the properties of bulk heterojunction solar cells have been investigated using the drift-diffusion model. It was observed that open circuit voltage and power conversion efficiency are affected by two loss mechanisms. The recombination of charge carriers in wrong contacts destroys photogenerated electron-hole pairs, and the bulk recombination increases the act of coupling between electron-hole pairs with different binding energies and consequently lowers the open circuit voltage. The first loss mechanism rises as the mobility of each of the two carriers increases. The bulk recombination not only depends on the slow carrier mobility but also affected by the mobility balance of two carriers. Thus, it generates two optimal points for power conversion efficiency at none unity electron to hole mobility ratio. In the active layer, light does not get absorbed uniformly, and the profile of the photogenerated excitons depends on the device thickness. Therefore, similar changes in the electron and hole mobility do not bring about the same changes in power conversion efficiency. Also, this study indicates that with the simultaneous increase of mobility and thickness, considerable enhancement in the efficiency of the bulk heterojunction solar cells would be achieved.

中文翻译：

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有机太阳能电池性能分析：光电建模与仿真

摘要 在本文中，使用漂移扩散模型研究了迁移率和活性层厚度对体异质结太阳能电池性能的影响。据观察，开路电压和功率转换效率受两种损耗机制的影响。错误接触中电荷载流子的复合破坏了光生电子 - 空穴对，并且体复合增加了具有不同结合能的电子 - 空穴对之间的耦合作用，从而降低了开路电压。第一种损耗机制随着两个载流子中每一个的迁移率的增加而增加。体复合不仅取决于慢载流子迁移率，还受两个载流子迁移率平衡的影响。因此，它在电子与空穴迁移率不为单位的情况下产生功率转换效率的两个最佳点。在有源层中，光不会被均匀吸收，光生激子的分布取决于器件厚度。因此，电子和空穴迁移率的类似变化不会带来功率转换效率的相同变化。此外，这项研究表明，随着迁移率和厚度的同时增加，体异质结太阳能电池的效率将得到显着提高。电子和空穴迁移率的类似变化不会带来功率转换效率的相同变化。此外，这项研究表明，随着迁移率和厚度的同时增加，体异质结太阳能电池的效率将得到显着提高。电子和空穴迁移率的类似变化不会带来功率转换效率的相同变化。此外，这项研究表明，随着迁移率和厚度的同时增加，体异质结太阳能电池的效率将得到显着提高。