Facile one-step growth and patterning of aligned squaraine nanowires via evaporation-induced self-assembly

A method is reported to investigate the growth, alignment, and periodic patterning of organic 1D single-crystal nanowires on a solid substrate. The method can be used to prepare the 2,4-bis[4-(N,N-dimethylamino)phenyl]squaraine (SQ) nanostructures by solvent evaporation on a horizontal substrates. The method used solvent-evaporation-induced self-assembly, contact line pinning, and dewetting to prepare nanostructures. A squaraine dye, 2,4-bis[4-(N,N- dimethylamino)phenyl]squaraine (SQ), and an organic semiconductors were used in the study. It was observed during the demonstration that the SQ molecules can form aggregates due to their strong intermolecular interactions between the acceptor and the donor groups. The study also found that the donor-acceptor dipole-dipole inter-molecular interactions can enhance the growth of 1D nanostructures.