Risø National Laboratory for Sustainable Energy, Technical University of Denmark, Frederiksborgvej 399, DK-4000 Roskilde, Denmark.
ACS Appl Mater Interfaces. 2009 Dec;1(12):2768-77. doi: 10.1021/am900518r.
The search for polymer solar cells giving a high open circuit voltage was conducted through a comparative study of four types of bulk-heterojunction solar cells employing different photoactive layers. As electron donors the thermo-cleavable polymer poly-(3-(2-methylhexyloxycarbonyl)dithiophene) (P3MHOCT) and unsubstituted polythiophene (PT) were used, the latter of which results from thermo cleaving the former at 310 degrees C. As reference, P3HT solar cells were built in parallel. As electron acceptors, either PCBM or bis-[60]PCBM were used. In excess of 300 solar cells were produced under as identical conditions as possible, varying only the material combination of the photo active layer. It was observed that on replacing PCBM with bis[60]PCBM, the open circuit voltage on average increased by 100 mV for P3MHOCT and 200 mV for PT solar cells. Open circuit voltages approaching 1 V were observed for the PT:bis[60]PCBM solar cells and a maximum conversion efficiency of 1.3% was obtained for solar cells with P3MHOCT:PCBM as the photoactive material. For the reference solar cells maximum efficiencies of 2.1 and 2.4% were achieved for P3HT:PCBM and P3HT:bis[60]PCBM, respectively. Despite special measures taken in terms of substrate design and device processing, a substantial spread in the photovoltaic properties was generally observed. This spread could not be correlated with the optical properties of the solar cells, the thickness of the photo active layer or the electrode deposition conditions of the aluminum top electrode.
通过对四种使用不同光活性层的体异质结太阳能电池进行比较研究，寻找开路电压较高的聚合物太阳能电池。作为电子给体，使用了热可裂解聚合物聚（3-（2-甲基己氧基羰基）噻吩）（P3MHOCT）和未取代的聚噻吩（PT），后者可在 310°C 时通过热裂解前者得到。作为参考，同时构建了 P3HT 太阳能电池。作为电子受体，使用了 PCBM 或双-[60]PCBM。在尽可能相同的条件下生产了超过 300 个太阳能电池，仅改变了光活性层的材料组合。观察到，用双-[60]PCBM 代替 PCBM 时，P3MHOCT 和 PT 太阳能电池的开路电压平均分别增加了 100mV 和 200mV。PT:双-[60]PCBM 太阳能电池的开路电压接近 1V，并且对于使用 P3MHOCT:PCBM 作为光活性材料的太阳能电池，获得了 1.3%的最大转换效率。对于参考太阳能电池，P3HT:PCBM 和 P3HT:双-[60]PCBM 的最大效率分别为 2.1%和 2.4%。尽管在衬底设计和器件处理方面采取了特殊措施，但通常观察到光伏性能有很大的差异。这种差异无法与太阳能电池的光学特性、光活性层的厚度或铝顶电极的电极沉积条件相关联。
