Nanostructured sexithiophene/clay hybrid mutilayers: A comparative structural and morphological characterization

Ultrathin films prepared from inorganic and organic materials are of increasing interest as hybrid nanocomposite materials. We have investigated for the first time the formation of nanostructured ultrathin films of montmorillonite clay (MONT) and a bicationic sexithiophene derivative (6TN) using the layer-by-layer self-assembly approach. The main goal is to investigate the structure and layer ordering of these films suitable for future applications in organic semiconductor devices. We have compared the structure and morphology of 6TN/MONT multilayer thin films prepared from pure water and 0.1 M NaCl systems. The 6TN amphiphile showed unique aggregation behavior both in solution and on the surface, which changes with the presence of salts and a THF cosolvent. On clay surfaces, the 6TN aggregates deposited from saline solutions have a more uniform size distribution and surface coverage than that from a pure water system. This was verified by UV-vis spectra, X-ray diffraction (XRD), and atomic force microscopy (AFM). The idea of incorporating more 6TN species absorbed on the surface while yielding a smoother surface morphology have a great significance in semiconductor device fabrication.