Novel supramolecular design strategies for mixed-stack charge transfer nanostructures

Abstract

One-dimensional (1-D) mixed stack charge transfer (CT) nanostructures, composed of alkyl tetrathiafulvalene dicarboxylate dipotassium salt derivatives (dbTTFS/ChdbTTFS) and unsymmetrical, dodecyl substituted naphthalene diimide (NDI-Cat) amphiphiles were constructed via non-covalent co-assembly process. Detailed spectroscopic measurements revealed efficient co-facial assembly between donor (D, dbTTFS/ Ch-dbTTFS) and acceptor (A, NDI-Cat) amphiphiles to form 1:1 superamphiphiles. NMR spectroscopy measurements provided insights into the face to face orientation of the D and A molecules in their co-assembly. This efficient D-A CT coassembly resulted in strong red shifted CT absorption in the near infra-red (NIR, 825 nm) region. Furthermore, two probe electrical measurements on these CT-nanostructures showed that they are semiconducting in nature and can further be useful for supramolecular electronics.