Cited by 3,378Thermal properties of materialsCarbon Nanotubes in CompositesGraphene research and applications

Thermal Transport Measurements of Individual Multiwalled Nanotubes

Open access
Kim, P., Shi, L., Majumdar, A., McEuen, P. L.·2001·Physical Review Letters

Abstract

The thermal conductivity and thermoelectric power of a single carbon nanotube were measured using a microfabricated suspended device. The observed thermal conductivity is more than 3000 W/K m at room temperature, which is 2 orders of magnitude higher than the estimation from previous experiments that used macroscopic mat samples. The temperature dependence of the thermal conductivity of nanotubes exhibits a peak at 320 K due to the onset of umklapp phonon scattering. The measured thermoelectric power shows linear temperature dependence with a value of 80 microV/K at room temperature.

AI snapshot

Written from the paper’s full text.

TL;DR

The authors measured thermal transport of an individual multiwalled carbon nanotube using a microfabricated suspended device, finding room-temperature thermal conductivity above 3000 W/m K and thermoelectric power of 80 µV/K. The thermal conductivity peaks at 320 K due to the onset of Umklapp phonon scattering.

Key findings

  • For a single MWNT of diameter 14 nm and bridging length 2.5 µm, the measured thermal conductance reaches a maximum of approximately 1.6 × 10⁻⁷ W/K near room temperature, and the derived thermal conductivity is more than 3000 W/m K at room temperature.
  • This room-temperature thermal conductivity is two orders of magnitude higher than the previous bulk mat estimate of 20 W/m K, an order of magnitude higher than an aligned SWNT sample value of 250 W/m K, and comparable to a theoretical expectation of 6000 W/m K.
  • The thermal conductivity increases with temperature, following a power law with exponent 2.50 for 8 K < T < 50 K, then approximately T² for 50 K < T < 150 K, and peaks at 320 K before decreasing rapidly; the crossover gives an estimated interlayer Debye temperature Θ⊥ = 50 K.
  • The thermoelectric power shows linear temperature dependence with a room-temperature value of 80 µV/K, and its positive sign indicates hole-like majority carriers.

Methods

  • Suspended devices were fabricated on a silicon nitride/silicon oxide/silicon multilayer, with two 10 µm × 10 µm silicon nitride membrane islands suspended by silicon nitride beams; Pt thin-film resistors on each island served as both heaters and thermometers.
  • A single MWNT was placed to bridge the two suspended islands by mechanical manipulation. Joule heating in one resistor created a temperature gradient, and the resulting temperature changes of both islands were measured from resistance changes versus applied power.
  • Thermal conductance was extracted using a simple heat-transfer model, and thermal conductivity was estimated assuming a solid isotropic material and neglecting junction thermal conductance. Thermoelectric power was obtained from the slope of thermoelectric voltage versus Joule heating power.

Limitations

  • Stated: the reported thermal conductivity is a lower bound because the authors neglect junction thermal conductance and assume a solid isotropic material to correct geometric factors; they note that further study is needed to analyze the contribution of individual MWNT layers.
  • Stated: below 8 K, both resistors saturate due to impurity scattering and cannot be used as temperature sensors; the diameter measurement has a resolution limit of 2 nm, which is the major uncertainty in κ.
  • Stated/evident: the TEP measurement may be affected by gas adsorption and oxygen doping because the MWNTs were exposed to air; the results are from a single MWNT, so generalization to other nanotubes or ensembles is not established in the text.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1103/physrevlett.87.215502

Cites

20 of 20 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

0 of 28 cited sources checked · 0 supported · 0 flagged

  • Findingcitation
    § Thermal Transport Measurements of Individual Multiwalled Nanotubes · p. 2

    The thermal conductance of the junction between a self-heated MWNT and a metal electrode at room temperature is ∼0.5 W/m K per unit length per unit temperature difference.

    “From our separate study of scanning thermal microscopy on a self heated MWNT[18], we have estimated the thermal conductance of the junction at room temperature; the heat flow rate from a unit length of the tube to metal electrode at a given unit junction temperature difference was found to be ∼ 0.5 W/m K.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [18]

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Findingown data
    § Thermal Transport Measurements of Individual Multiwalled Nanotubes · p. 3

    In the intermediate temperature range (50 K < T < 150 K), the thermal conductivity of the MWNT increases almost quadratically in T.

    “In the intermediate temperature range (50 K &lt; T &lt; 150 K), κ ( T ) increases almost quadratically in T (i.e., κ ( T ) ∼ T 2 ).”
    Quote in the paperSubstantial claim
  • Findingown data
    § Thermal Transport Measurements of Individual Multiwalled Nanotubes · p. 3

    Beyond the peak at 320 K, the thermal conductivity of the MWNT decreases rapidly.

    “Beyond this peak, κ ( T ) decreases rapidly.”
    Quote in the paperNot a substantial claim
  • Findingreasoning
    § Thermal Transport Measurements of Individual Multiwalled Nanotubes · p. 1

    The temperature dependence of the thermal conductivity of an individual MWNT exhibits a peak at 320 K.

    “The temperature dependence of the thermal conductivity of nanotubes exhibits a peak at 320 K due to the onset of Umklapp phonon scattering.”
    • Also stated in: § Thermal Transport Measurements of Individual Multiwalled Nanotubes · p. 3 · plain
      “Above this temperature range, κ ( T ) deviates from quadratic temperature dependence and has a peak at 320 K.”
    • Also stated in: § Thermal Transport Measurements of Individual Multiwalled Nanotubes · p. 4 · plain
      “The temperature dependence of the thermal conductivity shows a peak at 320 K due to the onset of Umklapp phonon scattering.”
    Quote in the paperSubstantial claim
  • Findingown data
    § Thermal Transport Measurements of Individual Multiwalled Nanotubes · p. 3

    At low temperatures (8 K < T < 50 K), the thermal conductivity of the MWNT increases following a power law with an exponent 2.50.

    “At low temperatures, 8 K &lt; T &lt; 50 K, κ ( T ) increases following a power law with an exponent 2.50.”
    Quote in the paperSubstantial claim
  • May combine two claims. 5
  • Classified as probably not a substantial claim. 2
  • May combine two claims.

    Findingown data
    § Thermal Transport Measurements of Individual Multiwalled Nanotubes · p. 2

    The thermal conductance of the single MWNT increases by several orders of magnitude as temperature is raised, reaching a maximum of approximately 1.6 × 10^-7 W/K near room temperature before decreasing at higher temperatures.

    “It increases by several orders of magnitude as the temperature is raised, reaching a maximum of approximately 1.6 × 10 -7 W/K near room temperature before decreasing again at higher temperatures.”
    Quote in the paperSubstantial claim
  • Classified as probably not a substantial claim.

    Premisecitation
    § Thermal Transport Measurements of Individual Multiwalled Nanotubes · p. 3

    The phonon thermal conductivity can be written as κ = ∑_p C_p v_p l_p, where C_p, v_p, and l_p are the specific heat capacity, phonon group velocity, and mean free path of phonon mode p.

    “In a simple model [22], the phonon thermal conductivity can be written as: κ = ∑ p C p v p l p , where C p , v p , and l p is the specific heat capacity, phonon group velocity, and the mean free path of phonon mode p .”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [22]

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Interpretationreasoning
    § Thermal Transport Measurements of Individual Multiwalled Nanotubes · p. 3

    The nearly ballistic phonon transport behavior was not seen in bulk experiments, possibly due to additional extrinsic phonon scattering mechanisms such as tube-tube interactions.

    “This remarkable behavior was not seen in the bulk experiments, possibly due to additional extrinsic phonon scattering mechanisms such as tube-tube interactions.”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Interpretationreasoning
    § Thermal Transport Measurements of Individual Multiwalled Nanotubes · p. 3

    At low temperatures, Umklapp scattering freezes out, so the phonon mean free path equals the static scattering length and κ(T) follows the temperature dependence of the specific heat.

    “At low temperatures, the Umklapp scattering freezes out, l = l st , and thus κ ( T ) simply follows the temperature dependence of C p 's.”
    Quote in the paperSubstantial claim
  • Classified as probably not a substantial claim.

    Premisecitation
    § Thermal Transport Measurements of Individual Multiwalled Nanotubes · p. 3

    The phonon mean free path consists of two contributions: l^-1 = l^-1_st + l^-1_um, where l_st and l_um are static and Umklapp scattering lengths.

    “The phonon mean free path consists of two contributions: l -1 = l -1 st + l -1 um where l st and l um are static and Umklapp scattering length, respectively.”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Interpretationreasoning
    § Thermal Transport Measurements of Individual Multiwalled Nanotubes · p. 3

    Below room temperature, where phonon-phonon Umklapp scattering is minimal, phonons have only a few scattering events between the thermal reservoirs and phonon transport is nearly ballistic.

    “Thus below room temperature where the phonon-phonon Umklapp scattering is minimal, phonons have only a few scattering events between the thermal reservoirs, and the phonon transport is 'nearly' ballistic.”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Premisecitation
    § Thermal Transport Measurements of Individual Multiwalled Nanotubes · p. 3

    As T exceeds the Debye temperature of the interlayer phonon mode, the interlayer phonon modes are fully occupied and κ(T) scales as T^2, indicating two-dimensional thermal conduction in a MWNT.

    “As T &gt; Θ ⊥ , the interlayer phonon modes are fully occupied, and κ ( T ) ∼ T 2 , indicative of the two dimensional nature of thermal conduction in a MWNT [24].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [24]

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

7 of 7
  • The authors state this as an assumption.

    The thermal conductivity estimate assumes a solid isotropic material to correct geometric factors.

    “In the following, however, we simply estimate the thermal conductivity neglecting the junction thermal conductance and assuming a solid isotropic material to correct geometric factors.”
  • The authors state this as an assumption.

    The thermal conductivity estimate neglects the junction thermal conductance.

    “In the following, however, we simply estimate the thermal conductivity neglecting the junction thermal conductance and assuming a solid isotropic material to correct geometric factors.”
  • The authors state this as an assumption.

    The MWNTs used in the experiments were exposed to air and presumably doped with oxygen.

    “The MWNTs used in our experiments were exposed in air and presumably doped with oxygen.”
3 of 3

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Suspending legs have two stated lengths

    Minor

    The device description says the suspending beams are 200 μm long, while the caption for the same device says its legs are 250 μm long.

1 of 1

Cites

Flagged first, then by citations

1 of the 21 references couldn’t be matched to a known paper.

Research works printed but not linked: 2

  1. M. Osman, 2001, Nanotechnology, 12, 21, 10.1088/0957-4484/12/1/305 · DOI
  2. B. T. Kelly, 1981, Physics of Graphite

Cited by

Sorted by citations

Authors
Kim, P., Shi, L., Majumdar, A., & McEuen, P. L.
Affiliations
  • University of California, Berkeley (US)
  • Lawrence Berkeley National Laboratory (US)
Venue
Physical Review Letters
Published
2001-10-31
Volume
87
Issue
21
Pages
215502-215502
ISSN
  • 0031-9007 (ISSN-L)
  • 1079-7114
OpenAlex
W2170116274
Cited by
3,378
References
21
Citations by year
2026: 58 · 2025: 83 · 2024: 80 · 2023: 114 · 2022: 138 · 2021: 167 · 2020: 142 · 2019: 182 · 2018: 218 · 2017: 168 · 2016: 177 · 2015: 174 · 2014: 172 · 2013: 205 · 2012: 209
FWCI
30.99
Type
journal article
Language
en
Open access
Locations
  • Physical Review Letters (publishedVersion)
  • PubMed (publishedVersion)
  • arXiv (Cornell University) (submittedVersion)
  • Technische Universität Dortmund Eldorado (Technische Universität Dortmund) (submittedVersion)
  • arXiv (Cornell University)
  • Technische Universität Dortmund Eldorado (Technische Universität Dortmund)
Topics
  • Physical Sciences › Materials Science › Materials Chemistry › Thermal properties of materials
  • Physical Sciences › Materials Science › Materials Chemistry › Carbon Nanotubes in Composites
  • Physical Sciences › Materials Science › Materials Chemistry › Graphene research and applications
Keywords
carbon nanotubes, multi-walled carbon nanotubes, thermal conductivity, thermoelectric power, temperature dependence, phonon transport

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