Liu Chao, Tan Yun, Li Chunquan, Wu Feiyan, Chen Lie, Chen Yiwang
College of Chemistry/Institute of Polymers, Nanchang University , 999 Xuefu Avenue, Nanchang 330031, China.
Department of Electronic Information Engineering, Nanchang University, Nanchang University , 999 Xuefu Avenue, Nanchang 330031, China.
ACS Appl Mater Interfaces. 2015 Sep 2;7(34):19024-33. doi: 10.1021/acsami.5b03340. Epub 2015 Aug 24.
Two novel liquid-crystal-conjugated polyelectrolytes (LCCPEs) poly[9,9-bis[6-(4-cyanobiphenyloxy)-hexyl]-fluorene-alt-9,9-bis(6-(N,N-diethylamino)-hexyl)-fluorene] (PF6Ncbp) and poly[9,9-bis[6-(4-cyanobiphenyloxy)-hexyl]-fluorene-alt-9,9-bis(6-(N-methylimidazole)-hexyl]-fluorene] (PF6lmicbp) are obtained by covalent linkage of the cyanobiphenyl mesogen polar groups onto conjugated polyelectrolytes. After deposition a layer of LCCPEs on ZnO interlayer, the spontaneous orientation of liquid-crystal groups can induce a rearrangement of dipole moments at the interface, subsequently leading to the better energy-level alignment. Moreover, LCCPEs favors intimate interfacial contact between ZnO and the photon harvesting layer and induce active layer to form the nanofibers morphology for the enhancement of charge extraction, transportation and collection. The water/alcohol solubility of the LCCPEs also enables them to be environment-accepted solvent processability. On the basis of these advantages, the poly(3-hexylthiophene) (P3HT):[6,6]-phenyl-C60-butyric acid methyl ester (PC60BM)-based inverted polymer solar cells (PSCs) combined with ZnO/PF6Ncbp and ZnO/PF6lmicbp bilayers boost the power conversion efficiency (PCE) to 3.9% and 4.2%, respectively. Incorporation of the ZnO/PF6lmicbp into the devices based on a blend of a narrow band gap polymer thieno[3,4-b]thiophene/benzodithiophene (PTB7) with [6,6]-phenyl C70-butyric acid methyl ester (PC71BM) affords a notable efficiency of 7.6%.
通过将氰基联苯介晶极性基团共价连接到共轭聚电解质上，获得了两种新型液晶共轭聚电解质（LCCPEs），即聚[9,9-双[6-(4-氰基联苯氧基)-己基]-芴-alt-9,9-双(6-(N,N-二乙氨基)-己基)-芴]（PF6Ncbp）和聚[9,9-双[6-(4-氰基联苯氧基)-己基]-芴-alt-9,9-双(6-(N-甲基咪唑)-己基)-芴]（PF6lmicbp）。在ZnO中间层上沉积一层LCCPEs后，液晶基团的自发取向可诱导界面处偶极矩的重排，进而实现更好的能级排列。此外，LCCPEs有利于ZnO与光子收集层之间形成紧密的界面接触，并诱导活性层形成纳米纤维形态，以增强电荷提取、传输和收集。LCCPEs的水/醇溶解性还使其具有环境友好的溶剂加工性能。基于这些优点，结合ZnO/PF6Ncbp和ZnO/PF6lmicbp双层的聚（3-己基噻吩）（P3HT）：[6,6]-苯基-C60-丁酸甲酯（PC60BM）基倒置聚合物太阳能电池（PSC）的功率转换效率（PCE）分别提高到3.9%和4.2%。将ZnO/PF6lmicbp引入基于窄带隙聚合物噻吩并[3,4-b]噻吩/苯并二噻吩（PTB7）与[6,6]-苯基-C70-丁酸甲酯（PC71BM）的共混物的器件中，可实现7.6%的显著效率。
