Campoy-Quiles Mariano, Ferenczi Toby, Agostinelli Tiziano, Etchegoin Pablo G, Kim Youngkyoo, Anthopoulos Thomas D, Stavrinou Paul N, Bradley Donal D C, Nelson Jenny
Department of Physics, Blackett Laboratory, Imperial College London, Prince Consort Road, London SW7 2BW, UK.
Nat Mater. 2008 Feb;7(2):158-64. doi: 10.1038/nmat2102. Epub 2008 Jan 20.
Control of blend morphology at the microscopic scale is critical for optimizing the power conversion efficiency of plastic solar cells based on blends of conjugated polymer with fullerene derivatives. In the case of bulk heterojunctions of regioregular poly(3-hexylthiophene) (P3HT) and a soluble fullerene derivative ([6,6]-phenyl C61-butyric acid methyl ester, PCBM), both blend morphology and photovoltaic device performance are influenced by various treatments, including choice of solvent, rate of drying, thermal annealing and vapour annealing. Although the protocols differ significantly, the maximum power conversion efficiency values reported for the various techniques are comparable (4-5%). In this paper, we demonstrate that these techniques all lead to a common arrangement of the components, which consists of a vertically and laterally phase-separated blend of crystalline P3HT and PCBM. We propose a morphology evolution that consists of an initial crystallization of P3HT chains, followed by diffusion of PCBM molecules to nucleation sites, at which aggregates of PCBM then grow.
在微观尺度上控制共混物形态对于优化基于共轭聚合物与富勒烯衍生物共混物的塑料太阳能电池的功率转换效率至关重要。对于区域规整的聚（3-己基噻吩）（P3HT）和可溶性富勒烯衍生物（[6,6]-苯基C61-丁酸甲酯，PCBM）的本体异质结，共混物形态和光伏器件性能都受到各种处理的影响，包括溶剂的选择、干燥速率、热退火和气相退火。尽管这些方法有很大差异，但各种技术报道的最大功率转换效率值相当（4-5%）。在本文中，我们证明这些技术都导致了组分的一种共同排列，即由结晶P3HT和PCBM组成的垂直和横向相分离的共混物。我们提出了一种形态演变，包括P3HT链的初始结晶，随后PCBM分子扩散到成核位点，然后PCBM聚集体在这些位点生长。
