Fast Assembly of Cyanine Dyes into Aggregates onto [6,6]-Phenyl C61-Butyric Acid Methyl Ester Surfaces from Organic Solvents
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- 作者：Jakob Heier ; Rolf Steiger ; Frank Nesch ; Roland Hany
- 刊名：Langmuir
- 出版年：2010
- 出版时间：March 16, 2010
- 年：2010
- 卷：26
- 期：6
- 页码：3955-3961
- 全文大小：944K
- 年卷期：v.26,no.6(March 16, 2010)
- ISSN：1520-5827
文摘
Supramolecular agglomerates of organic colorants based on noncovalent interactions are promising candidates for the development of sensors, optoelectronics, lighting, or photovoltaics. However, their fast and defect-free fabrication on large scales using low-cost technologies has proven elusive so far. Here, we introduce a so far unreported mechanism to induce molecular order in cyanine dyes within minutes from organic solvents by self-assembly. Spin coating blends of a cyanine dye and a soluble fullerene derivative ([6,6]-phenyl C61-butyric acid methyl ester (PCBM)) from apolar, aprotic solvents leads to phase-separated structures on the micrometer scale. With this superordinated phase structure, adjustment of dye aggregation is possible, leading to novel optical properties of the film emerging from dye self-assembly on the nanometer scale. In the primary process, semiporous PCBM domains act as nucleation sites for H-aggregates. H-aggregates can then be reconstructed into J-aggregates by dissolving PCBM from the film. Unexpectedly, the method even works for sterically hindered cyanine dyes that are known for their reduced tendency to aggregate. Additionally, selective removal of H-aggregates leaves a template of PCBM nanocrystals, onto which cyanine dye monomers readsorb from solution, forming H-aggregates of similar quality.