Self-assembly of two-dimensional nanostructures of linear regioregular poly(3-hexylthiophene)

Two dimensional poly(3-hexylthiophene) (P3HT) nanosheets were prepared by evaporation of a diluted mixture of solvent. The dimension and size of the nanostructures was controlled by tuning the good-to-poor solvent ratio. The morphology and structure of the nanosheets were fully characterized. Atomic Force Microscopy (AFM) characterization showed the nanosheets were lamellar structures with a thickness of about 3-5 nm of a single layer. The anisotropic arrangement of P3HT was clearly defined by selected area electron diffraction. In the nanostructures, P3HT adopted the edge on orientation with the pi-pi stacking direction parallel to the substrate and the alkyl side chains perpendicular to the substrate. Single nanosheet showed a typical anisotropic charge carrier transport property.