P3HT:DiPBI bulk heterojunction solar cells: morphology and electronic structure probed by multiscale simulation and UV/vis spectroscopy.
P3HT:DiPBI bulk heterojunction solar cells: morphology and electronic structure probed by multiscale simulation and UV/vis spectroscopy.
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DOI：
10.1039/c5cp06704a
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发表时间：
2016-02
期刊：
影响因子：
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通讯作者：
T. Winands;M. Böckmann;T. Schemme;Phong-Minh Timmy Ly;D. H. de Jong;Zhaohui Wang;C. Denz;A. Heuer;N. Doltsinis
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文献类型：
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作者：
T. Winands;M. Böckmann;T. Schemme;Phong-Minh Timmy Ly;D. H. de Jong;Zhaohui Wang;C. Denz;A. Heuer;N. Doltsinis
对聚(3-己基噻吩基)(P3HT)和二茂联二亚胺(DiPBI)的混合物进行了粗粒分子动力学模拟。研究了不同的退火和冷却方式对晶体形貌的影响，并分析了形成的磁畴结构。特别是，观察到了π堆积的双铅分子团簇，其大小随着温度的升高而减小。磁区结构和扩散系数数据表明，DiPBI子系统在700-900K之间经历了有序→无序相变，在将粗晶模型反向映射到建立在第一性原理基础上的原子力场表示后，进行了基于密度泛函理论的电子结构计算。用含时密度泛函线性响应理论计算了P3HT：DiPBI混合物的UV/Vis吸收光谱，并对旋涂薄膜进行了实验记录。结果表明，吸收光谱敏感地依赖于非晶态结构的细节，从而提供了对形貌的有价值的洞察。结果表明，回火工艺对材料的电学性质有显著影响。这些知识可能有助于开发有效的处理程序，以提高体异质结太阳能电池的性能。
Coarse grained molecular dynamics simulations are performed for a mixture of poly(3-hexylthiophene) (P3HT) and diperylene bisimide (DiPBI). The effect of different annealing and cooling protocols on the morphology is investigated and the resulting domain structures are analyzed. In particular, π-stacked clusters of DiPBI molecules are observed whose size decreases with increasing temperature. Domain structure and diffusivity data suggest that the DiPBI subsystem undergoes an order → disorder phase transition between 700 and 900 K. Electronic structure calculations based on density functional theory are carried out after backmapping the coarse grained model onto an atomistic force field representation built upon first principles. UV/vis absorption spectra of the P3HT:DiPBI mixture are computed using time-dependent density functional linear response theory and recorded experimentally for a spin-coated thin film. It is demonstrated that the absorption spectrum depends sensitively on the details of the amorphous structure, thus providing valuable insight into the morphology. In particular, the results show that the tempering procedure has a significant influence on the material's electronic properties. This knowledge may help to develop effective processing routines to enhance the performance of bulk heterojunction solar cells.