Rojas Geoffrey A, Wu Yanfei, Haugstad Greg, Frisbie C Daniel
Department of Chemical Engineering and Materials Science, University of Minnesota , 421 Washington Avenue SE, Minneapolis, Minnesota 55455, United States.
Characterization Facility, University of Minnesota , 100 Union Street SE, Minneapolis, Minnesota 55455, United States.
ACS Appl Mater Interfaces. 2016 Mar 9;8(9):5772-6. doi: 10.1021/acsami.6b00367. Epub 2016 Feb 29.
Scanning Kelvin probe microscopy was used to measure band-bending at the model donor/acceptor heterojunction poly(3-hexylthiophene) (P3HT)/fullerene (C60). Specifically, we measured the variation in the surface potential of C60 films with increasing thicknesses grown on P3HT to produce a surface potential profile normal to the substrate both in the dark and under illumination. The results confirm a space-charge carrier region with a thickness of 10 nm, consistent with previous observations. We discuss the possibility that the domain size in bulk heterojunction organic solar cells, which is comparable to the space-charge layer thickness, is actually partly responsible for less than expected electron/hole recombination rates.
扫描开尔文探针显微镜用于测量模型供体/受体异质结聚（3-己基噻吩）（P3HT）/富勒烯（C60）处的能带弯曲。具体而言，我们测量了在P3HT上生长的厚度不断增加的C60薄膜的表面电势变化，以生成在黑暗和光照条件下垂直于衬底的表面电势分布图。结果证实了存在一个厚度为10 nm的空间电荷载流子区域，这与之前的观察结果一致。我们讨论了本体异质结有机太阳能电池中的畴尺寸与空间电荷层厚度相当，实际上可能部分导致电子/空穴复合率低于预期的可能性。
