Surface treatment by binary solvents induces the crystallization of a small molecular donor for enhanced photovoltaic performance.
Surface treatment by binary solvents induces the crystallization of a small molecular donor for enhanced photovoltaic performance.
复制标题
DOI：
10.1039/c5cp05644f
复制
发表时间：
2016-01
期刊：
影响因子：
--
通讯作者：
Weihua Zhou;Yuanpeng Xie;Xiaotian Hu;Lin Zhang;Xiangchuan Meng;Yong Zhang;Wei Ma;Yiwang Chen
中科院分区：
文献类型：
--
作者：
Weihua Zhou;Yuanpeng Xie;Xiaotian Hu;Lin Zhang;Xiangchuan Meng;Yong Zhang;Wei Ma;Yiwang Chen
用甲醇（MeOH）和1-氯萘（CN）组成的二元溶剂对活性层进行表面处理，可以有效地将p-DTS(FBTTh2)2:PC71BM基小分子太阳能电池的功率转换效率（PCE）从2.4%提高到6.5%。研究了p-DTS(FBTTh2)2:PC71BM薄膜的光学性质和形貌。原子力显微镜（AFM）和透射电子显微镜（TEM）显示，MeOH:CN二元溶剂处理可以显著增强活性层的吸收，形成更多的p-DTS(FBTTh2)2纳米原纤维，结晶度更高。二维掠入射广角x射线散射（GIWAXS）结果进一步表明，二元溶剂处理后，p-DTS(FBTTh2)2分子的分子堆积明显增强。相比之下，原始甲醇对p-DTS(FBTTh2)2:PC71BM体系的晶体结构、相分离和光伏性能没有显著影响，表明CN溶剂在诱导p-DTS(FBTTh2)2分子结晶过程中起主要作用。
The surface treatment of the active layer with binary solvents composed of methanol (MeOH) and 1-chloronaphthalene (CN), was demonstrated to effectively improve the power conversion efficiency (PCE) from 2.4% to 6.5% for p-DTS(FBTTh2)2:PC71BM based small molecular solar cells. The optical properties and morphology of the p-DTS(FBTTh2)2:PC71BM films were carefully investigated. The results indicate that treatment with MeOH:CN binary solvents could significantly enhance the absorption of the active layer, due to the formation of more p-DTS(FBTTh2)2 nanofibrils associated with higher crystallinity as revealed by atomic force microscopy (AFM) and transmission electron microscopy (TEM). The two-dimensional grazing incidence wide-angle X-ray scattering (GIWAXS) results further demonstrate that the molecular packing of p-DTS(FBTTh2)2 molecules could be strongly enhanced after treatment with the binary solvents. In contrast, pristine methanol shows no significant influence on the crystalline structure, phase separation or the photovoltaic properties of the p-DTS(FBTTh2)2:PC71BM system, showing that the CN solvent plays the main role in inducing the crystallization of p-DTS(FBTTh2)2 molecules.