Highly Stable Dispersion of Carbon Nanotubes in Deep Eutectic Solvent for the Preparation of CNT‐Embedded Carbon Xerogels for Supercapacitors

Abstract

The current study reports a kind of ternary deep eutectic solvent (DES) based on choline chloride, urea, and glycerol for the dispersion of multi‐walled carbon nanotubes (MWCNT) in the presence of surfactant. MWCNT‐embedded organic gels were subsequently prepared from the polymerization of resorcinol and formaldehyde in the obtained MWCNT‐dispersed DES. It has been demonstrated that the as‐prepared DES is excellent in dispersing and stabilizing the MWCNT, and thus allows the in situ synthesis of MWCNT functionalized resorcinol‐formaldehyde xerogels with no visible phase‐separation during the long sol‐gel process. After ambient drying and carbonization, MWCNTs can be well dispersed within the carbon xerogel matrix. The obtained carbon material possesses increased electrical conductivity while preserves the well‐developed porous structure. When used as electrodes in supercapacitors, it exhibits enhanced capacitance as well as rate performance. The specific capacitance at 0.5 A g−1 was 228 F g−1, 22 % more capacitance than that of the pristine carbon xerogel. More remarkably, it provides the electrodes with more than 200 % enhancement in capacitance when compared with that of the MWCNT‐embedded carbon xerogel prepared in aqueous solvent under the same conditions.

Deep Eutectic Solvent Assisted Dispersion of Carbon Nanotubes in Water

“…The authors are unable to find any similar work where DES is systematically studied to disperse carbon nanotubes in water. Chen et al dispersed multiwalled carbon nanotubes in ChCl-Gly-Urea DES in the presence of sodium dodecyl sulfate an anionic surfactant (Chen et al, 2019). However, their work cannot be compared due to the difference in materials (multiwalled vs. single walled carbon nanotubes), different DES (ChCl-Gly-Urea vs. ChCl-Gly), presence of surfactant, and absence of quantitative data (particle size, particle size distribution, dispersion quality, etc.)…”

Characterization of Carbon Nanomaterials Dispersions: Can Metal Decoration of MWCNTs Improve Their Physicochemical Properties?

“…Several studies have been carried out regarding the thermophysical properties of several ILs and DES [ 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 ], and both have been proved to be good dispersant media for CNTs dispersion [ 21 , 34 , 35 , 36 , 37 , 38 , 39 ].…”

Insights on (C, BN, Si, Ge, MoS2) Nanotubes in Reline Deep Eutectic Solvent

“…The suitability of DESs for nanotechnology applications has been confirmed, including for the development of nanoscale and functional materials and production and application of new materials . Carbon nanotube (CNT) applications in DESs have been considered, including CNT surface functionalization as well as the development of stable dispersions . In particular, the development of highly stable CNT dispersions in DESs has been probed to be useful for the development of thermal applications, with the advantageous use of DESs as base fluids in comparison with conventional fluids such as ethylene glycol considering DESs’ almost negligible evaporation (very low vapor pressure), low corrosion, and large thermal stability .…”

“…In particular, the development of highly stable CNT dispersions in DESs has been probed to be useful for the development of thermal applications, with the advantageous use of DESs as base fluids in comparison with conventional fluids such as ethylene glycol considering DESs’ almost negligible evaporation (very low vapor pressure), low corrosion, and large thermal stability . There are only a handful of published works on CNT solvation by DES molecules and DESs confined in CNT cavities, properties of DESs at CNT surfaces, and the developed intermolecular forces. , Therefore, further studies are required in order to establish an understating on the subject and open the floor for applications of these systems at the industrial level.…”

“…32 Carbon nanotube (CNT) applications in DESs have been considered, including CNT surface functionalization 33 as well as the development of stable dispersions. 34 In particular, the development of highly stable CNT dispersions in DESs has been probed to be useful for the development of thermal applications, 35 with the advantageous use of DESs as base fluids in comparison with conventional fluids such as ethylene glycol considering DESs' almost negligible evaporation (very low vapor pressure), 36 low corrosion, 37 and large thermal stability. 38 There are only a handful of published works on CNT solvation by DES molecules and DESs confined in CNT cavities, properties of DESs at CNT surfaces, and the developed intermolecular forces.…”