Sreedhar Ram Kiran, Mehdizadeh-Rad Hooman, Ompong David, Setsoafia Daniel Dodzi Yao, Singh Jai
College of Engineering, IT and Environment, Purple 12, Charles Darwin University, Darwin, NT 0909, Australia.
Energy and Resources Institute, Charles Darwin University, Darwin, NT 0909, Australia.
Nanomaterials (Basel). 2021 Jan 15;11(1):209. doi: 10.3390/nano11010209.
In this paper, characterisation of exciton generation is carried out in three bulk-heterojunction organic solar cells (BHJ OSCs)-OSC1: an inverted non-fullerene (NF) BHJ OSC; OSC2: a conventional NF BHJ OSC; and OSC3: a conventional fullerene BHJ OSC. It is found that the overlap of the regions of strong constructive interference of incident and reflected electric fields of electromagnetic waves and those of high photon absorption within the active layer depends on the active layer thickness. An optimal thickness of the active layer can thus be obtained at which this overlap is maximum. We have simulated the rates of total exciton generation and position dependent exciton generation within the active layer as a function of the thicknesses of all the layers in all three OSCs and optimised their structures. Based on our simulated results, the inverted NF BHJ OSC1 is found to have better short circuit current density which may lead to better photovoltaic performance than the other two. It is expected that the results of this paper may provide guidance in fabricating highly efficient and cost effective BHJ OSCs.
在本文中，对三种体异质结有机太阳能电池（BHJ OSCs）进行了激子产生特性研究——OSC1：一种倒置非富勒烯（NF）BHJ OSC；OSC2：一种传统NF BHJ OSC；以及OSC3：一种传统富勒烯BHJ OSC。研究发现，电磁波的入射电场和反射电场的强相长干涉区域与有源层内高光子吸收区域的重叠取决于有源层厚度。因此，可以获得一个有源层的最佳厚度，此时这种重叠最大。我们模拟了所有三种OSC中有源层内总激子产生速率和位置相关激子产生速率随所有层厚度的变化，并优化了它们的结构。基于我们的模拟结果，发现倒置NF BHJ OSC1具有更好的短路电流密度，这可能使其光伏性能优于其他两种电池。预计本文的结果可为制造高效且经济高效的BHJ OSCs提供指导。
