摘要
Introducing liquid-crystalline small-molecule donors(SMDs)into binary systems based on the strong intermolecular interactions of SMDs is a facile and effective strategy to tune the active layer morphology and improve the performance of organic solar cells(OSCs).Contrary to conventional understanding,this research proposes a new strategy for ternary OSCs implicating that"weakly crystalline materials can also optimize the morphology of the active layer and improve the OSCs performance".Herein,we designed and synthesized two liquid-crystalline SMDs,Z1 and Z2,based on benzodifuran(BDF)units.The amorphous Z2-incorporated ternary devices present an unexpectedly improved power conversion efficiency(PCE)>18%with good stability.By contrast,the highly ordered Z1-based ternary devices possess a significantly depressed efficiency.Multiple characterizations reveal that the Z2-based ternary blend films possess improved miscibility and efficient charge transport.This novel strategy for the selection of the third component is significant for the fabrication of high-efficiency ternary OSCs.
将具有高迁移率和强分子间作用的液晶小分子引入有机光伏器件活性层中被认为是一种提升光电转换效率的有效策略.不同于常规的认识,本文展示了“弱结晶材料同样能优化活性层形貌和提升光伏器件效率”的三元有机光伏器件调控新策略.本文设计合成了两个基于苯并二呋喃给体单元的液晶小分子Z1和Z2,发现具有无序堆积特性的Z2基三元有机光伏器件展现出了更高的光电转换效率(Z2:PM6:BTP-eC9,PCE:18.12%;Z2:PM6:Y6,PCE:17.66%)和更优异的器件稳定性.而基于高度有序的Z1的三元有机光伏器件却表现出明显降低的能量转换效率.光电器件和活性层薄膜形貌的协同表征说明Z2基三元体异质结薄膜的高光电效率主要归因于其更优的电荷传输效率和更合适的相分离尺度.该研究工作展示的有机光伏器件第三组分的调控新策略对新型高效光伏器件的制备具有重要的指导意义.
作者
Yuchen Yue
Bing Zheng
Mengdi Liu
Yujie Chen
Lijun Huo
Jingxia Wang
Lei Jiang
岳钰琛;郑冰;刘梦迪;陈雨洁;霍利军;王京霞;江雷(CAS Key Laboratory of Bioinspired Smart Interfacial Science Technical Institute of Physics and Chemistry,Chinese Academy of Sciences,Beijing 100190,China;School of Chemistry,Beihang University,Beijing 100190,China;School of Future Technology,University of Chinese Academy of Sciences(UCAS),Beijing 100049,China;Ji Hua Laboratory,Foshan 528000,China)
基金
the Ministry of Science and Technology of China(2017YFA0204504)
the National Natural Science Foundation of China(51873221,52073292,51673207,21774003,and 51373183)
Chinese Academy of Sciences and Dutch Research Project(1A111KYSB20190072)
Beijing Municipal Science&Technology Commission(Z181100004418012)
Beijing Natural Science Foundation(2212032).
