A new approach for the achievement of stable aqueous dispersions of carbon nanotubes

Abstract

A simple and innovative way to achieve highly stable aqueous dispersions of both multi- and single-walled carbon nanotubes is reported.

The role of functionalization on the colloidal stability of aqueous fullerene C60 dispersions prepared with fullerides

“…Due to the low degree of functionalization and to their non-re-dispersibility after water addition (see Figure 4), dispersions 1d are lyophobic and the colloidal stability of those is provided by electrostatic repulsion. [19,[42][43][44][45] So, these dispersions can be considered as model to apply DLVO theory for carbon-based systems, [30] as has been done for fullerene dispersions made by other routes. [3,19,[44][45][46] Figure 5A presents a graphic of total interaction energy (U T ) as a function of distance for two identical spherical particles calculated based on DLVO theory, [47,48] considering the experimental radius (half of the diameters shown in Table S1) and zeta potentials for 1d dispersions, an approximate value for Hamaker constant (1 x 10 -19 J) from literature, [3] and 1:1 electrolyte (1 .…”

“…A yellowish colour is typically observed for dispersions of fullerenes. [19][20][21][22][23] Herein, we report (i) the re-examination of the oxidation step of fulleride solutions that leads to the generation of metastable dispersions in THF, (ii) the transfer to water, producing, aqueous dispersions of C 60 , in analogy to aqueous dispersions of graphene [27,28] and carbon nanotubes, [29,30] (iii) that these dispersions are stable regardless of the presence or not of functionalized fullerenes (e.g. fullerenols).…”

Liquid–liquid interfaces: a unique and advantageous environment to prepare and process thin films of complex materials

“…The obtained film was modified with tetraphenylporphyrin and the photocurrent generation was demonstrated. 36 Films based on carbon nanostructures have been prepared starting from either the carbon nanomaterials initially dispersed in an organic solvent 31,32 or in water, 37 evidencing the amplitude of the technique. The effect of previous chemical treatment on the samples, aiming at (i) purification (through the chemical dissolution/etching of side-products); (ii) chemical modification of the surface, or (iii) adding functionalities to stabilize the solid in dispersions, has also been demonstrated.…”

Quick and Surfactant-Free Dispersion of Various Carbon Nanoparticles in Aqueous Solution as Casting Technique for Devices

“…The dispersion in THF was added to water, and after THF evaporated, an aqueous dispersion containing C 60 nanoparticles was obtained, which was stable for several months [24]. Similarly, Damasceno et al also presented a simple and effective method for preparing single-and multiwalled carbon nanotubes for stable water dispersion based on a dispersion previously prepared in tetrahydrofuran containing phenol that provides electrons to the nanotubes and colloidal stability through electrostatic repulsion [25].…”