Non-covalent functionalization of single walled carbon nanotubes with Fe-/Co-porphyrin and Co-phthalocyanine for field-effect transistor applications

Abstract

This work reports the non-covalent functionalization of SWNTs with Fe-porphyrin, Co-porphyrin and Co-phthalocyanine molecules. The functionalized SWNTs were first characterized using Raman and X-ray photoelectron spectroscopies. Observations down to nanoscale resolution were also performed by atomic force microscopy, as well as scanning and transmission electron microscopies. The spectroscopic methods evidenced an electronic interaction between the metal-centered molecules and the SWNTs, ensuring the robustness of the functionalization. High resolution microscopy characterizations reveal that the porphyrin and phthalocyanine molecules are adsorbed on the surface of SWNTs. The electrical characterizations show a weak charge transfer between those grafted molecules and the SWNTs, confirming the electronic interaction between the molecules and the SWNTs. Density functional theory (DFT) supports experimental data and helps understanding the experimental results of selective interaction of metal complexes with one type of semiconducting SWNTs. • The non-covalent assembly of metalloporphyrin (MPo) and metallophthalocyanines (MPc) onto CNTFETs. • These molecules strongly bind to the side walls of SWNTs via physi-adsorption and п-п interactions. • The theoretical study evidences that the molecules are electron donors and the SWNTs are n-doped. • The electrical measurements showed a charge transfer between the metal-centered molecules and SWNTs.