Improved conduction in transparent single walled carbon nanotube networks drop-cast from volatile amine dispersions

Ravi, Shrividya; Kaiser, A. B.; Bumby, Chris W.

doi:10.1016/j.cplett.2010.06.084

Cited by 22 publications

(34 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In our earlier study [14], we found evidence (in a single sample) of an additional term consistent with thermal activation. The conductance of our present set of samples is well fitted by the full conduction expression in Eq.…”

mentioning

confidence: 59%

“…For samples following 2D VRH, the T 0 parameter can be calculated as 1.7 ± 0.8 eV. This characteristic barrier size distribution can be attributed to the nanotube network alone in our samples due to the complete removal of solvents by heating [14]. That is, localization here corresponds to physical parameters, e.g., defects [21] related to nanotubes rather than the solvent residue.…”

Section: Original Papermentioning

confidence: 97%

See 1 more Smart Citation

Charge transport in surfactant‐free single walled carbon nanotube networks

Ravi

Kaiser

Bumby³

2013

Physica Status Solidi (b)

Self Cite

View full text Add to dashboard Cite

Conduction in thin random networks of single‐walled carbon nanotubes (SWNTs) is typically dominated by metallic SWNT segments and limited by variable‐range hopping (VRH) in disordered junction regions. However, in our surfactant‐free networks, we show that in parallel with VRH there is another mode of conduction involving both semiconducting and metallic SWNTs. This second process showing activated behavior makes a substantial contribution to conductance at higher temperatures, with similar activation energies in different samples despite a large variation in overall magnitude of the conductivity. From the magnitude of the activation energy (0.160.05\,eV), we ascribe this additional term to activation across Schottky barriers between metallic and semiconducting SWNTs in conducting paths involving a small number of semiconducting SWNTs. The Mott parameters for VRH are also independent of the overall conductivity, indicating that the local structure of intertube contacts between metallic SWNTs in the most conductive paths is also similar in samples of different overall conductivity.

show abstract

mentioning

confidence: 59%

Section: Original Papermentioning

confidence: 97%

Charge transport in surfactant‐free single walled carbon nanotube networks

Ravi

Kaiser

Bumby³

2013

Physica Status Solidi (b)

Self Cite

View full text Add to dashboard Cite

show abstract

“…In agreement with a previous report, the temperature-dependant electrical transport measurements revealed a dominant VRH mechanism in the range T=4-225 K with a divergence in the range T=225-300 K, figure. 2 [38]. This divergence has the form of an additional thermally activated component, (1) where the first term is the Mott hopping formula with =1/(d+1) and d is the dimensionality of the hopping (i.e.…”

Section: Resultsmentioning

confidence: 99%

“…The influence of surfactant on the host SWNT networks was minimised by using a volatile 1:7 volume mixture of n-butylamine: tetrahydrofuran as dispersant and solvent together with a post-deposition annealing process [38]. The resultant sparse networks comprised well-defined SWNT bundles of diameter 30±10 nm mainly confined to the plane of the substrate covering about 65% of the glass surface, figure.…”

Section: Resultsmentioning

confidence: 99%

High electrical conductance enhancement in Au-nanoparticle decorated sparse single-wall carbon nanotube networks

McAndrew

Baxendale

2013

Nanotechnology

View full text Add to dashboard Cite

We report high electrical conductivity enhancement in sparse single-walled carbon nanotube networks by decoration with Au nanoparticles. The optimised hybrid network exhibited a sheet resistance of 650 /sq: 1/1500 of the resistance of the host undecorated network, with a negligible optical transmission penalty (>90% transmittance at 550 nm wavelength). The electrical transport at room temperature in host and decorated networks was dominated by 2-dimensional variable range hopping.The high conductance enhancement was due to positive charge transfer from the decorating Au nanoparticles in intimate contact with the host network causing a Fermi energy shift into the high density of states at a van Hove singularity and enhanced electron delocalisation relative to the host network which beneficially modifies the hopping parameters in such a way that the network behaves as an integral whole. The effect is most pronounced when the nanoparticle diameter is comparable to the electron mean free path in the bulk material at room temperature and there is minimum nanoparticle agglomeration. For higher than optimal values of nanoparticles per unit area or nanoparticle diameter, the conductivity enhancement is countered by metallic inclusions in the current pathways that are of higher resistance than the VRH-controlled elements.

show abstract

“…Beside this, the chemical doping mechanism in the acid-treated network is found to be responsible for the metallike linear resistivity dependence in a broad temperature range. S. Ravi et al [74] fabricated thin film of SWNTs by the drop casting method from SWNT dispersions in the volatile organic solvent, nbutylamine. Removal of this solvent by a simple annealing leads to substantial improvements in both transparency and conductivity of films.…”

Section: Variable Range Hopping In Single-walled Carbon Nanotubesmentioning

confidence: 99%

Variable Range Hopping in Carbon Nanotubes

Khan¹,

Husain

2010

CNANO

View full text Add to dashboard Cite

Carbon nanotubes exhibit exceptional properties that are a consequence of their symmetric structure. Many properties of carbon nanotubes (CNTs) have been explained in the wider context of materials science, thereby highlighting the contribution from different researchers worldwide in this rapidly expanding field. Among various other properties of CNTs studied so far, the electrical transport properties are still unclear and needs a lot of attention. Due to high anisotropy of graphite, the electrical properties are strongly dependent on the structure of the nanotubes. Since, the CNTs can be metallic and semi-conducting in nature, their explanation to electrical conduction mechanism in these two cases would be different. During the last few years, efforts have been made to understand the electrical transport phenomenon in CNTs, aiming at the design of nanoelectronic devices made solely of carbon. Keeping in view the above, it is of great interest to present a state of art on the progress involving the research work on electrical conduction mechanism especially variable range hopping in CNTs. In the present paper, we have presented a review on electrical transport mechanism especially variable range hopping in carbon nanotubes. This review will provide a better understanding of variable range hopping in CNTs.

show abstract

Improved conduction in transparent single walled carbon nanotube networks drop-cast from volatile amine dispersions

Cited by 22 publications

References 36 publications

Charge transport in surfactant‐free single walled carbon nanotube networks

Charge transport in surfactant‐free single walled carbon nanotube networks

High electrical conductance enhancement in Au-nanoparticle decorated sparse single-wall carbon nanotube networks

Variable Range Hopping in Carbon Nanotubes

Contact Info

Product

Resources

About