Zhang Zhenzhen, Feng Liuliu, Xu Shutao, Liu Ye, Peng Hongjian, Zhang Zhi-Guo, Li Yongfang, Zou Yingping
College of Chemistry and Chemical Engineering Central South University Changsha 410083 China.
Beijing National Laboratory for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China.
Adv Sci (Weinh). 2017 Aug 17;4(11):1700152. doi: 10.1002/advs.201700152. eCollection 2017 Nov.
A new small molecule acceptor, m-ITIC-OR, based on indacenodithieno[3,2-]thiophene core with -alkoxyphenyl side chains, is designed and synthesized. The m-ITIC-OR film shows broader and redshift absorption compared to its solution and matched energy levels with a hexafluoroquinoxaline-based polymer donor-HFQx-T. Here, polymer solar cells (PSCs) by blending an HFQx-T donor and an m-ITIC-OR acceptor as an active layer deliver the power conversion efficiency (PCE) of 6.36% without any posttreatment. The investigations demonstrate that the HFQx-T:m-ITIC-OR blend films possess higher and more balanced charge mobility, negligible bimolecular recombination, and nanoscale interpenetrating morphology after thermal annealing (TA) treatment. Through a simple TA treatment at 150 °C for 5 min, an impressive PCE of 9.3% is obtained. This efficiency is among one of the highest PCEs for additive free PSCs. This is the first time alkoxyphenyl side chain is introduced into nonfullerene electron acceptor; more interestingly, the new electron acceptor (m-ITIC-OR) in this work shows a great potential for highly efficient photovoltaic properties.
设计并合成了一种基于茚并二噻吩并[3,2-b]噻吩核且带有烷氧基苯基侧链的新型小分子受体m-ITIC-OR。与溶液相比，m-ITIC-OR薄膜表现出更宽且红移的吸收，并且与基于六氟喹喔啉的聚合物给体HFQx-T的能级相匹配。在此，通过将HFQx-T给体和m-ITIC-OR受体混合作为活性层制备的聚合物太阳能电池（PSC），无需任何后处理即可实现6.36%的功率转换效率（PCE）。研究表明，HFQx-T:m-ITIC-OR共混薄膜在热退火（TA）处理后具有更高且更平衡的电荷迁移率、可忽略不计的双分子复合以及纳米级互穿形态。通过在150℃下简单热退火5分钟，可获得令人印象深刻的9.3%的PCE。该效率是无添加剂PSC的最高PCE之一。这是首次将烷氧基苯基侧链引入非富勒烯电子受体；更有趣的是，这项工作中的新型电子受体（m-ITIC-OR）在高效光伏性能方面显示出巨大潜力。
