Kanal Ilana Y, Owens Steven G, Bechtel Jonathon S, Hutchison Geoffrey R
Department of Chemistry, University of Pittsburgh, 219 Parkman Avenue, Pittsburgh, Pennsylvania 15260, United States.
J Phys Chem Lett. 2013 May 16;4(10):1613-23. doi: 10.1021/jz400215j. Epub 2013 Apr 29.
There has been increasing interest in rational, computationally driven design methods for materials, including organic photovoltaics (OPVs). Our approach focuses on a screening "pipeline", using a genetic algorithm for first stage screening and multiple filtering stages for further refinement. An important step forward is to expand our diversity of candidate compounds, including both synthetic and property-based measures of diversity. For example, top monomer pairs from our screening are all donor-donor (D-D) combinations, in contrast with the typical donor-acceptor (D-A) motif used in organic photovoltaics. We also find a strong "sequence effect", in which the average HOMO-LUMO gap of tetramers changes by ∼0.2 eV as a function of monomer sequence (e.g., ABBA versus BAAB); this has rarely been explored in conjugated polymers. Beyond such optoelectronic optimization, we discuss other properties needed for high-efficiency organic solar cells, and applications of screening methods to other areas, including non-fullerene n-type materials, tandem cells, and improving charge and exciton transport.
人们对包括有机光伏（OPV）在内的材料的合理、计算驱动的设计方法越来越感兴趣。我们的方法侧重于一种筛选“流程”，在第一阶段筛选中使用遗传算法，并在多个过滤阶段进行进一步优化。向前迈出的重要一步是扩大我们候选化合物的多样性，包括基于合成和性质的多样性度量。例如，我们筛选出的顶级单体对都是供体-供体（D-D）组合，这与有机光伏中使用的典型供体-受体（D-A）基序形成对比。我们还发现了一种强烈的“序列效应”，即四聚体的平均HOMO-LUMO能隙随单体序列（例如ABBA与BAAB）变化约0.2 eV；这在共轭聚合物中很少被研究。除了这种光电优化之外，我们还讨论了高效有机太阳能电池所需的其他特性，以及筛选方法在其他领域的应用，包括非富勒烯n型材料、串联电池以及改善电荷和激子传输。
