Formation, Structure, and Function of Hydrogenated and Fluorinated Long‐Chain Phosphonate‐Modified Single‐Walled Carbon Nanotubes with Bidentate Bonds

Abstract The dispersion of hydrophilized single‐walled carbon nanotube (SWCNT) in organic solvent, through the modification of its surface by bidentate long‐chain phosphonic acid with excellent heat resistance, and its structural characterization, through the formation of a monolayer on the water surface, have been performed. The surface‐modified chains were developed by both hydrocarbon‐based and fluorocarbon‐based modifiers, and the arrangement of the organized films of each modified SWCNT was evaluated. The modified nanotubes were uniformly dispersed in toluene solvent, facilitating the confirmation of its lipophilicity, and spread as a monolayer at the air–water interface. The morphology of the organo‐SWCNT monolayer was fibrous. In the Raman spectrum of the modified‐SWCNT Langmuir‐Blodgett multilayers, the defect‐derived D band shifted to lower wavenumbers. The above experimental results confirmed the non‐desorptive property of the modified‐bidentate chain. The packing and orientation of the modified chains were evaluated through out‐of‐plane and in‐plane X‐ray diffraction and polarized infrared spectroscopy. In addition, the monolayer of organo‐SWCNT was densified with a small number of defects by the “repeating compression‐expansion method”. Furthermore, activation of the lysozyme enzyme from the subphase caused adsorption and immobilization onto organo‐SWCNT monolayers. The introduction of SWCNTs to the air–water interface has revealed the potential for nanostructural control and the estimation of interactions between biomolecules.