Selective Wrapping of Few-Walled Carbon Nanotubes by a Serpent-Like Heterobimetallic Coordination Polymer

In this work, selective interactions between the constituents of the composite CNT@MnCu (2) prepared using carbon nonotubes (CNTs) (1) and the heterobimetallic chain [MnCu(opba)]n (MnCu), opba = o-phenylenebis(oxamate), were studied mainly by resonance Raman spectroscopy and high-resolution transmission electron microscopy (HRTEM). An apparent interaction between CNTs and MnCu complex with the wrapping of the former by the heterobimetallic complex was observed in the microscopy images. The resonance Raman data suggest that the interations between MnCu complex and the CNTs are selective, occurring mainly with metallic CNTs independently of the diameter and excitation energy. However, for semiconducting CNTs, these interactions solely occur with tubes having diameters higher than ca. 1.47 nm.