Manipulating Crystallization Kinetics of Conjugated Polymers in Nonfullerene Photovoltaic Blends toward Refined Morphologies and Higher Performances
Manipulating Crystallization Kinetics of Conjugated Polymers in Nonfullerene Photovoltaic Blends toward Refined Morphologies and Higher Performances
复制标题
控制非富勒烯光伏共混物中共轭聚合物的结晶动力学以获得精细的形态和更高的性能
DOI：
10.1021/acs.macromol.0c02872
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发表时间：
2021
期刊：
影响因子：
5.5
通讯作者：
Liu Feng
中科院分区：
文献类型：
--
作者：
Zhan Junzhe;Wang Lei;Zhang Ming;Zhu Lei;Hao Tianyu;Zhou Guanqing;Zhou Zichun;Chen Jiajun;Zhong Wenkai;Qiu Chaoqun;Leng Shifeng;Zou Yecheng;Shi Zhiwen;Zhu Haiming;Feng Wei;Zhang Maojie;Li Yongfang;Zhang Yongming;Liu Feng
在有机光伏器件（OPV）中引入溶剂添加剂已成为优化有源层形貌以实现高功率转换效率的常用方法。了解添加剂如何优化薄膜纳米结构形成的机制，如结晶动力学和相分离，是普遍感兴趣的。在目前的手稿中，国家的最先进的非富勒烯体异质结共混物，PM 6：IT-4F混合物，用于狭缝模头涂布实验。1，8-辛二硫醇（DIO）辅助制造导致功率转换效率（PCE）从10.11%显著增加到12.67%。激子解离和载流子输运也得到了改善，这在很大程度上与形态改善有关。采用原位掠入射广角X射线散射（GIWAXS）研究了不同工艺条件下PM 6：IT-4F成膜过程中的时间分辨结晶动力学，观察到了详细的聚合物原纤形态。Johnson-Mehl-Avrami-Kolmogorov（JMAK）结晶分析提供了这样的见解，即少量DIO添加剂的添加不仅会增加成核和生长阶段期间的成核速率，而且还会通过突发成核介导的结晶向晶界诱导的结晶阶段变化引入次级原纤晶体完整性。这些观察结果可能对OPV社区在操纵印刷太阳能电池形态和效率以实现商业应用方面具有普遍意义。
The introduction of solvent additives has become a general approach in optimizing the active layer morphology in organic photovoltaics (OPV) to achieve high power conversion efficiency. It is of general interest to understand the mechanism of how additives optimize the thin-film nanostructure formation such as crystallization kinetics and phase separation. In the current manuscript, state-of-the-art nonfullerene bulk heterojunction blends, PM6:IT-4F mixture, are used in a slot-die coating experiment. The 1,8-octanedithiol (DIO)-aided fabrication leads to a significant increase in the power conversion efficiency (PCE) from 10.11 to 12.67%. Exciton dissociation and carrier transport have also been improved, largely associated with morphology improvement. Time-resolved crystallization kinetics during PM6:IT-4F film formation under different processing conditions was studied by in situ grazing-incidence wide-angle X-ray scattering (GIWAXS), in which a detailed polymer fibril morphology formation was seen. The Johnson–Mehl–Avrami–Kolmogorov (JMAK) crystallization analysis affords insights that the addition of the DIO additive in a small amount would not only increase the nucleation rate during the nucleation and growth stage but also introduce secondary fibril crystal perfection via burst nucleation-mediated crystallization to a grain boundary-induced crystallization stage change. These observations can be of general interest to the OPV community in manipulating the printed solar cell morphology and efficiency toward the commercial application.