Diameter-selective non-covalent functionalization of carbon nanotubes with porphyrin monomers.

F Vialla (1) , G Delport (2) , Y Chassagneux (1) , Ph Roussignol (1) , Jean‐sébastien Lauret (2) , C Voisin (1)

1 LPA - Laboratoire Pierre Aigrain
2 LAC - Laboratoire Aimé Cotton

We report on the spontaneous noncovalent functionalization of carbon nanotubes with hydropho-bic porphyrin molecules in micellar aqueous solution. By monitoring the species concentrations with optical spectroscopies, we can follow the kinetics of the reaction and study its thermodynamical equilibrium as a function of the reagent concentrations. We show that the reaction is well accounted for by a cooperative Hill equation, reaching a molecular coverage close to a compact monolayer for a porphyrin concentration larger than a diameter-specific threshold concentration. The equilibrium constant is measured for 16 nanotube chiral species. The Gibbs energy of the reaction (of the order of-40 kJ/mol) and its evolution with the nanotube diameter is consistent with theoretical calculations of the binding energy. This thermodynamical study shows a strong preferential binding of TPP molecules to larger diameter nanotubes. This original curvature selectivity can be used to induce diameter selective species enrichment.

Domaines: Autre [cond-mat.other]

F Vialla, G Delport, Y Chassagneux, Ph Roussignol, Jean‐sébastien Lauret, et al.. Diameter-selective non-covalent functionalization of carbon nanotubes with porphyrin monomers.. Nanoscale, 2016, 8, pp.2326. ⟨10.1039/C5NR08023A⟩. ⟨hal-01250180⟩