Charge Photogeneration and extraction in polymer: fullerene bulk heterojunction organic solar cells

该项目旨在深入了解决定新型聚合物光伏效率的过程：富勒烯系统超越了研究充分的参考系统P3 HT：PCBM。特别是聚合物C-PCPDTBT和Si-PCPDTBT，以及一些新型的高效苯并二噻吩基共聚物，将进行研究。研究小组将进行各种实验，包括稳态和瞬态实验，如i.）偏压相关瞬态泵浦-探测光谱，ii.）场依赖时间分辨光致发光实验，iii.）延时采集现场实验，iv.）（时延）飞行时间（TOF）和v.）photo-CELIV实验这些实验应该直接观察电场对早期（fs-ns）电荷产生动力学和（成对）复合动力学以及（非成对）电荷复合和提取动力学的影响，时间尺度从纳米到毫秒。实验的结果将进行比较的界面激子解离过程和电荷扩散的微观模拟的理论研究。此外，将实验获得的参数输入宏观器件模拟，以将预测的JV曲线与实验获得的曲线进行比较，从而评估计算和建模方法的质量。

This project aims at gaining a profound understanding of the processes that determine the photovoltaic efficiency of novel polymer:fullerene systems beyond the well-studied reference system P3HT:PCBM. In particular the polymers C-PCPDTBT and Si-PCPDTBT, as well as some novel high-efficiency benzoditiophene-based copolymers, will be studied. The research team will perform various kinds of experiments including steady-state and transient experiments such as i.) biasdependent transient pump-probe spectroscopy, ii.) field-dependent time-resolved photoluminescence experiments, iii.) time-delayed collection field experiments, iv.) (time-delayed) time-of-flight (TOF) and v.) photo-CELIV experiments. These experiments are supposed to directly observe the effect of an electric field on the early-time (fs-ns) charge generation dynamics and (geminate) recombination dynamics as well as on the (non-geminate) charge recombination and extraction dynamics on a timescale from nano- to milliseconds. The results of the experiments will be compared to theoretical studies of the interfacial exciton dissociation process and microscopic simulations of charge diffusion. Furthermore, the experimentally obtained parameters will be entered into macroscopic device simulations to compare the predicted JV-curves with the experimentally obtained ones in order to evaluate the quality of the calculations and modelling approaches.