Tuning electrical and thermal connectivity in multiwalled carbon nanotube buckypaper

Abstract

We find that the electrical and thermal connectivity in multiwalled carbon nanotube buckypaper can be tuned using a spark plasma sintering (SPS) technique. Elevated SPS temperatures promote the formation of inter-tube connections and consequently impact the electrical resistivity, thermoelectric power and thermal conductivity of the buckypaper. In particular, the electrical resistivity as a function of SPS temperature exhibits a percolation-type behavior while the low temperature lattice thermal conductivity shows a crossover behavior in the sample dimensionality. The results are discussed in terms of the quasi-one-dimensional metallic nature of multiwalled carbon nanotubes, the packing density and the electron-phonon coupling.

Paper Electronics

“…Many applications have been considered, due to the potentially high electrical and thermal conductivity and strength, but the volume resistivity of buckypaper is typically several orders of magnitude higher than that of a single CNT and the cost is also an important issue. [ 65 ] Paper sheets made of graphene and graphene oxide have also been fabricated with a resulting conductivity of up to 120 S cm − 1 after a heat treatment at 220 ° C. [ 16 b] Conducting (1-10 S cm − 1 ) polymer-paper composite materials have been achieved by polymerizing polypyrrole and polyaniline onto cellulose and paper substrates. [ 66 , 67 ] Conductivities of up to 20 S cm − 1 have been reported by using a polyelectrolyte multilayer approach of covering the cellulose fi bers with PEDOT:PSS and CNT:PSS.…”

Strain engineering for thermal conductivity of single-walled carbon nanotube forests

“…Tubes in the SWCNT mat are randomly orientated, leading to the lose of SWCNT's advanced properties. For instance, the room temperature thermal conductivity in the SWCNT mat is typically in the range of 10 À1 to 10 Wm À1 K À1 , which is several orders lower than the SWCNT [7][8][9][10][11][12][13][14].…”

“…Great progress has been achieved in recent years toward the http://dx.doi.org/10.1016/j.carbon.2014. 10.006 0008-6223/Ó 2014 Elsevier Ltd. All rights reserved. E-mail address: jwjiang5918@hotmail.com C A R B O N 8 1 ( 2 0 1 5 ) 6 8 8 -6 9 3 Av ai la bl e at w w w .…”

3D Nanocomposites of Covalently Interconnected Multiwalled Carbon Nanotubes with SiC with Enhanced Thermal and Electrical Properties

“…[ 23 ] The SiC-CNT composite that we have fabricated has an optimum value of electrical conductivity, integrating the properties of electrically insulating SiC and conductive CNT. [ 32,33,38 ] From the TGA curve of the SiC-CNT sample (see the Supporting Information for more details), we witness a weight loss of ≈30% close to 600 °C. This is an indicative of the amount of residual graphitic carbon content in the sample after the sintering process.…”

“…There are reports of CNT blocks sintered using SPS without the addition of any matrix material having thermal conductivity values in the range of 12 W m −1 K −1 . [ 32 ] In this case, a percolation network of CNT is believed to create a 3D phonon conduction mechanism when high sintering temperatures (>1500 °C) are employed. In the present work, the creation of intertube and SiC-CNT junctions has a combinatorial effect on the thermal properties.…”