Template-synthesized nanostructure morphology influenced by building block structure

Abstract

We report the synthesis and characterization of a series of nanostructures and determine whether several distinct types of building blocks can be fashioned into linear nanostructures using hard-templates and electrochemical methods. We determine the aspects of molecular structure that influence morphology and propose a mechanism whereby morphology changes as a function of building block. We show how hydrophobic side-chains, such as 3-hexyl and 3-(2-ethyl)hexyl, can be used to prepare nanostructures with a geometry that is different from the shape of the template from which they derive. These nanostructures exhibit collapsed, nonlinear, and nonrigid shapes as observed by SEM and TEM. Hydrophilic side-chains such as 3-(2-(2-(2-ethoxy)ethoxy)ethoxy)methyl and 3-(hydroxy)methyl lead to linear nanostructures. We are also able to prepare linear nanostructures composed of the narrow HOMO–LUMO gap heterocycles selenophene and thieno[3,2-b]thiophene. The results open up many new opportunities for preparing nanostructures with greater complexity, functionality, and distinct optical properties that are imparted by their building block.