Tuning nanotubular structures by templateless electropolymerization with thieno[3,4-b]thiophene-based monomers with different substituents and water content

Abstract

Here, templateless electropolymerization is employed to produce nanotubular structures from various thieno[3,4-b]thiophene-based monomers that differ in substituent structure and size, as well as the linker connecting the thieno[3,4-b]thiophene core and substituent. The formation of densely packed vertically aligned are obtained from monomers with a pyrene substituent and when a significant amount of water (CH₂Cl₂ + H₂O) is included in the solvent. The geometrical parameters of the nanotubes are highly dependent on the electopolymerization method. A significant amount of air is trapped within the structure of the densely packed open nanotubes obtained with Qs = 100 mC cm^-2 causing an increase in water contact angle (θ_w) up to 82.6° (intermediate state between the Wenzel and the Cassie-Baxter state), and θ_w can become even more hydrophobic by further modifying the deposition method or the electrolyte.

Keywords: Conducting polymers; Electrochemistry; Nanostructures; Nanotubes; Wettability.