Sánchez Fernando, Sánchez Vicenta, Wang Chumin
Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico.
Departamento de Física, Facultad de Ciencias, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico.
Nanomaterials (Basel). 2021 Feb 16;11(2):495. doi: 10.3390/nano11020495.
Understanding the exciton dissociation process in organic solar cells is a fundamental issue for the design of high-performance photovoltaic devices. In this article, a parameterized quantum theory based on a coarse-grained tight-binding model plus non-local electron-hole interactions is presented, while the diffusion and recombination of excitons are studied in a square lattice of excitonic states, where a real-space renormalization method on effective chains has been used. The Hamiltonian parameters are determined by fitting the measured quantum efficiency spectra and the theoretical short-circuit currents without adjustable parameters show a good agreement with the experimental ones obtained from several polymer:fullerene and polymer:polymer heterojunctions. Moreover, the present study reveals the degree of polymerization and the true driving force at donor-acceptor interface in each analyzed organic photovoltaic device.
理解有机太阳能电池中的激子解离过程是设计高性能光电器件的一个基本问题。在本文中，提出了一种基于粗粒化紧束缚模型加非局域电子 - 空穴相互作用的参数化量子理论，同时在激子态的方形晶格中研究了激子的扩散和复合，其中在有效链上采用了实空间重整化方法。哈密顿量参数通过拟合测量的量子效率光谱来确定，并且理论短路电流在没有可调参数的情况下与从几种聚合物：富勒烯和聚合物：聚合物异质结获得的实验值显示出良好的一致性。此外，本研究揭示了每个分析的有机光伏器件中供体 - 受体界面处的聚合度和真正驱动力。
