Processing of Composite Electrodes of Carbon Nanotube Fabrics and Inorganic Matrices via Rapid Joule Heating

Abstract

Composites of nanocarbon network structures are interesting materials, combining mechanical properties and electrical conductivity superior to those of granular systems. Hence, they are envisaged to have applications as electrodes for energy storage and transfer. Here, we show a new processing route using Joule heating for a nanostructured network composite of carbon nanotube (CNT) fabrics and an inorganic phase (namely, MoS 2 ), and then study the resulting structure and properties. To this end, first, a unidirectional fabric of conductive CNT bundles is electrochemically coated with MoS 2 . Afterward, the conformally coated inorganic phase is crystallized via heat generated by direct current passing through the CNT ensemble. The Joule heating process is rapid (maximum heating rate up to 31.7 °C/s), enables accurate temperature control, and takes only a few minutes. The resulting composite material combines a high electrical conductivity of up to 1.72 (±0.25) × 10 5 S/m, tensile modulus as high as 8.82 ± 5.5 GPa/SG, and an axial tensile strength up to 200 ± 58 MPa/SG. Both electrical and mechanical properties are orders of magnitude above those of wet-processed nanocomposites of similar composition. The extraordinary longitudinal properties stem from the network of interconnected and highly aligned CNT bundles. Conductivity and modulus follow approximately a rule of mixtures, similar to a continuous fiber composite, whereas strength scales almost quadratically with the mass fraction of the inorganic phase due to the inorganic constraining realignment of CNTs upon stretching. This processing route is applicable to a wide range of nanocarbon-based composites with inorganic phases, leading to composites with specific strength above steel and electrical conductivity beyond the threshold for electronic limitations in battery electrodes.

Smart and Multifunctional Fiber‐Reinforced Composites of 2D Heterostructure‐Based Textiles

“…Joule heating also provides a direct path for inside‐out crystallization of the conformal MoS 2 layer, enabling excellent interfacial interaction between the MoS 2 and the underlying carbon‐based material (e.g., 2D graphene). [ 71 ] Due to extremely quick heating, simple processing, and ability to integrate with textiles [ 70 ] and other components, [ 72 ] in our study we investigated various configurations of graphene and MoS 2 heterostructure layers to create conductive heating textiles where glass fiber fabric was coated with these 2D materials (Figure 4b).…”

Rapid Carbonization of Anthracite Coal via Flash Joule Heating for Sodium Ion Storage

“…Some studies have reported that introducing an electric field during heating can effectively enhance the material's conductivity. 15,16 In this study, Joule heating was employed to achieve rapid temperature elevation. Among various Joule heating devices, 17,18 to allow current to pass through the carbon material, we adopted the flash Joule heating (FJH) method reported by Tour's team, 19 which boasts rapid reaction time and high reaction temperatures.…”

“…Moreover, the conductivity of carbon materials from direct pyrolysis is unsatisfactory, failing to meet the demands of high-rate charging and discharging. Some studies have reported that introducing an electric field during heating can effectively enhance the material’s conductivity. , …”

Applications of solar thermal radiation in a bio‐convective Eyring–Powell hybrid nanofluid flow under the influence of electro‐magnetohydrodynamics near a stagnation point: An irreversibility study

“…The use of Joule heating methodology of flash heating with has a unique kind of technique which produce nanoparticles mixing in well dispersed way. Upama et al [29] investigated joule heating for electrodes of nanotube and inorganic matrices with composite electrodes. Celik et al [30] discussed joule heating numerically and experimental investigations are also done for carbon fibre powder epoxy.…”