Future Industries Institute, University of South Australia , Adelaide, SA 5095, Australia.
Chemistry and Chemical Engineering, Chalmers University of Technology , SE-41296 Göteborg, Sweden.
ACS Appl Mater Interfaces. 2017 Mar 29;9(12):10929-10936. doi: 10.1021/acsami.6b12687. Epub 2017 Mar 14.
Poly(4-vinylpyridine) (P4VP) was used as a cathode interface layer in inverted organic solar cells (OSCs) fabricated using poly[2,3-bis(3-octyloxyphenyl)quinoxaline-5,8-diyl-alt-thiophene-2,5-diyl] (TQ1) and PCBM (phenyl C butyric acid methyl ester) as the donor and acceptor materials, respectively. We successfully demonstrate that the work function of underlying indium tin oxide (ITO) electrode can be significantly reduced by ∼0.7 eV, after modification of the surface with a thin film of P4VP. Photoconversion efficiency of 4.7% was achieved from OSCs incorporating P4VP interface layer between the ITO and bulk heterojunction (BHJ). Thin P4VP layer, when used to modify ZnO electron transport layer in inverted OSCs, reduced the ZnO work function from 3.7 to 3.4 eV, which resulted in a noteworthy increase in open-circuit voltage from 840 to 890 mV. On simultaneous modification of ZnO with P4VP and optimization of the BHJ morphology by using solvent additive chloronapthalene, photoconversion efficiency of OSCs was significantly increased from 4.6% to 6.3%. The enhanced device parameters are also attributed to an energetically favorable material stratification, as a result of an enrichment of PCBM toward the P4VP interface.
聚(4-乙烯基吡啶)（P4VP）被用作倒置有机太阳能电池（OSC）的阴极界面层，该电池使用聚[2,3-双（3-辛氧基苯基）喹喔啉-5,8-二基--alt-噻吩-2,5-二基]（TQ1）和 PCBM（苯丁酸甲酯）分别作为给体和受体材料。我们成功地证明，通过在 ITO 电极表面修饰一层 P4VP 薄膜，可以将 ITO 电极的功函数显著降低约 0.7eV。在包含 P4VP 界面层的 OSC 中，光电转换效率达到了 4.7%。当将薄 P4VP 层用于修饰倒置 OSC 中的 ZnO 电子传输层时，将 ZnO 的功函数从 3.7 降低到 3.4eV，这导致开路电压从 840mV 显著增加到 890mV。通过同时用 P4VP 修饰 ZnO 并通过使用溶剂添加剂氯萘优化 BHJ 形态，OSC 的光电转换效率从 4.6%显著提高到 6.3%。增强的器件参数还归因于能量有利的材料分层，这是由于 PCBM 向 P4VP 界面的富集。
