Analysis and modification of defective surface aggregates on PCDTBT:PCBM solar cell blends using combined Kelvin probe, conductive and bimodal atomic force microscopy

Beilstein Journal of Nanotechnology

关键词: conductive atomic force microscopy;    Kelvin probe force microscopy;    multifrequency AFM;    organic photovoltaics;    polymer solar cells;    surface defects;   

DOI  :  10.3762/bjnano.8.62

学科分类：地球科学(综合)

来源: Beilstein - Institut zur Foerderung der Chemischen Wissenschaften

【 摘 要 】

Organic photovoltaic systems comprising donor polymers and acceptor fullerene derivatives are attractive for inexpensive energy harvesting. Extensive research on polymer solar cells has provided insight into the factors governing device-level efficiency and stability. However, the detailed investigation of nanoscale structures is still challenging. Here we demonstrate the analysis and modification of unidentified surface aggregates. The aggregates are characterized electrically by Kelvin probe force microscopy and conductive atomic force microscopy (C-AFM), whereby the correlation between local electrical potential and current confirms a defective charge transport. Bimodal AFM modification confirms that the aggregates exist on top of the solar cell structure, and is used to remove them and to reveal the underlying active layer. The systematic analysis of the surface aggregates suggests that the structure consists of PCBM molecules.

【 授权许可】

CC BY