(Invited) Single-Walled Carbon Nanotubes Charge Management by Controlled Functionalization

Abstract

Managing the density of charges in carbon nanotubes opens new ways to tune their optical response, their transport properties, and their physico-chemical features. Charge transfer from molecules adsorbed onto the sidewall or filled within the hollow cavity of the nanotubes has already been demonstrated, yet a fine-tunable control of the surface coverage/filling fraction (and thus the amount of transferred charge) remains challenging to achieve. Alternatively, we developed an optically non-perturbing covalent functionalisation technique based on the inclusion of a triazine derivative into the carbon network. The nitrogen atom sustaining the attached group becomes an integrated part of the π-conjugated network and contributes with its lone electron pair to uplifting the position of the Fermi level of the tube. Since the density of attached groups can be varied by adapting the synthetic conditions, this technique offers the advantage of controlling the amount of charge injected into the tubes. Here we focus on a novel class of charge-transfer agents that either donate or withdraw electrons depending on the arrangements of their building units and how they affect the tubes features.