Hydrogen-bond acidic functionalized carbon nanotubes (CNTs) with covalently-bound hexafluoroisopropanol groups

Hydrogen-bond acidic fluoroalcohol groups are directly attached to the backbone of single walled carbon nanotubes (SWCNTs) via carbon–carbon bonds without the introduction of intermediate heteroatoms. Hexafluoroisopropanol functional groups are exceptionally strong hydrogen-bond acids, and are added to the nanotube surface (via the substituted benzene para position) as 2-phenyl-1,1,1,3,3,3-hexafluoro-2-propanol (i.e., –(p-C6H4)C(CF3)2OH) using the aryl diazonium approach to create hydrogen-bond acidic carbon nanotube (CNT) surfaces. These groups can promote strong hydrogen-bonding interactions with matrix materials in composites or with molecular species to be adsorptively concentrated and sensed. In the latter case, this newly developed material could potentially find useful application in chemical sensors and in CNT-based preconcentrator devices for the detection of hydrogen-bond basic analytes such as chemical warfare agents and explosives, as has been demonstrated for fluoroalcohol-containing polymers.