Carbon-assisted catalyst pretreatment enables straightforward synthesis of high-density carbon nanotube forests

Dee, Nicholas T.; Li, Jinjing; White, Alvin Orbaek; Jacob, Christophe; Shi, Wenbo; Kidambi, Piran R.; Cui, Kehang; Zakharov, Dmitri N.; Janković, Nina Z.; Bedewy, Mostafa; Chazot, Cécile A. C.; Carpena‐Núñez, Jennifer; Maruyama, Benji; Stach, Eric A.; Plata, Desirée L.; Hart, A. John

doi:10.1016/j.carbon.2019.06.083

Cited by 34 publications

(33 citation statements)

References 51 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Each concentration of PS, and control, were grown three times to ensure trends were valid for each series. No noticeable effect or carbothermal reduction from the aging of the quartz tube was identified [25] (Figure SI1).…”

Section: The Synthesis Of Carbon Nanotubesmentioning

confidence: 98%

Synthesis of Carbon Nanotubes via Liquid Injection Chemical Vapour Deposition as a Vector for the Chemical Recycling of Waste Composite Carbon Sources

White¹,

Hedayati²,

Yick³

et al. 2021

Preprint

Self Cite

View full text Add to dashboard Cite

For every three people on the planet there is approximately two Tonne (Te) of available plastic waste. We show that carbon recovery from polystyrene (PS) plastic is enhanced by the co-addition to solvents to grow carbon nanotubes (CNTs) by liquid injection chemical vapour deposition. Polystyrene was loaded up to 4 wt% in toluene and heated to 780 °C in the presence of a ferrocene catalyst and a hydrogen/argon carrier gas in a 1:19 ratio. High resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and Raman spectroscopy were used to identify multi-walled carbon nanotubes (MWCNTs). The PS addition in the range from 0 to 4 wt% showed improved quality and CNT homogeneity; Raman “Graphitic/Defective” (G/D) values increased from 1.9 to 2.3; mean CNT diameters increased from 43.0 to 49.2 nm; and maximum CNT yield increased from 11.3% to 14.2%. Since both the CNT diameters and the percentage yield increased with respect to polystyrene addition, we conclude that carbon from the PS contributes to the carbon within the MWCNTs. The electrical contact resistance of acid washed Bucky papers produced from each loading, ranged from 2.2 to 4.4 Ohm, with no direct correlation to PS loading. Due to this narrow range, the materials with different loading were mixed to create six wires of an Ethernet cable and tested using iPerf to give uplink and downlink speeds of ~99.5 Mbps, comparable to Cu wire of identical dimension (~99.5 Mbps). The lifecycle assessment (LCA) of CNT wire production was compared to copper wire production for the use case in a Boeing 747-400 over the lifespan of the craft. Due to their lightweight nature the CNT wires decreased the CO2 footprint by 21 kTonne (kTe) over the aircraft lifespan.

show abstract

Section: The Synthesis Of Carbon Nanotubesmentioning

confidence: 98%

Synthesis of Carbon Nanotubes via Liquid Injection Chemical Vapour Deposition as a Vector for the Chemical Recycling of Waste Composite Carbon Sources

White¹,

Hedayati²,

Yick³

et al. 2021

Preprint

Self Cite

View full text Add to dashboard Cite

show abstract

“…The mechanism of removing the carbon coating around the catalyst nanoparticles [ 47 , 48 ] is an enlightening strategy for increasing the ratio of active catalyst nanoparticle as well. Recently, Dee et al [ 49 ] proposed to pretreat the catalyst nanoparticles with trace exposures of carbon during the initial stage of annealing of the catalyst film. By optimizing the duration of carbon exposure, they achieved 8 times higher CNT density relative to a reference growth process condition.…”

Section: Synthesis Of High-density Cnt Arraymentioning

confidence: 99%

“…While only a few works achieved the synthesis of CNT at 350 °C using CMOS-compatible methods. Vollebregt et al [ 49 ] reported the synthesis of vertically aligned CNT array at 350 °C using the Co-Al alloy catalyst. At 350 °C, the CNT array synthesized with Co-Al catalyst showed a tube density of 5 × 10 10 cm −2 .…”

Section: Low-temperature Synthesis Of Cnt Arraymentioning

confidence: 99%

Synthesis of Vertical Carbon Nanotube Interconnect Structures Using CMOS-Compatible Catalysts

Zhou

et al. 2020

Nanomaterials

View full text Add to dashboard Cite

Synthesis of the vertically aligned carbon nanotubes (CNTs) using complementary metal-oxide-semiconductor (CMOS)-compatible methods is essential to integrate the CNT contact and interconnect to nanoscale devices and ultra-dense integrated nanoelectronics. However, the synthesis of high-density CNT array at low-temperature remains a challenging task. The advances in the low-temperature synthesis of high-density vertical CNT structures using CMOS-compatible methods are reviewed. Primarily, recent works on theoretical simulations and experimental characterizations of CNT growth emphasized the critical roles of catalyst design in reducing synthesis temperature and increasing CNT density. In particular, the approach of using multilayer catalyst film to generate the alloyed catalyst nanoparticle was found competent to improve the active catalyst nanoparticle formation and reduce the CNT growth temperature. With the multilayer catalyst, CNT arrays were directly grown on metals, oxides, and 2D materials. Moreover, the relations among the catalyst film thickness, CNT diameter, and wall number were surveyed, which provided potential strategies to control the tube density and the wall density of synthesized CNT array.

show abstract

“…They pointed out that low concentrations of oxygen can boost Ostwald ripening of Fe catalyst nanoparticles, which can be reduced by H 2 [13]. Carpena-N uñez et al [14] and Dee et al [15] showed that trace carbon residues on reactor walls influence the growth as well. Therefore, some universally applicable processing steps are required to reduce the adverse impact of uncontrolled quantities of chemical species on the consistency of CNT forest growth.…”

Section: Introductionmentioning

confidence: 99%

Reducing Variability in Chemical Vapor Deposition of Carbon Nanotubes Based on Gas Purification and Sample Support Redesign

Tomaraei

Lee

Abdulhafez

et al. 2021

Journal of Micro and Nano-Manufacturing

Self Cite

View full text Add to dashboard Cite

The synthesis of vertically aligned carbon nanotubes (CNTs), also referred to as CNT forest, by chemical vapor deposition (CVD) is an intricate process that is sensitive to multiple factors other than control of temperature, pressure, and gas flows. In particular, growth is highly sensitive to factors like ambient humidity, as well as small quantities of oxygen-containing species and carbon deposits inside the reactor. These typically uncontrolled factors significantly affect growth reproducibility and hinders the fundamental study of process-structure-property relationship for these emerging materials. Accordingly, universally applicable design modifications and process steps toward improving growth consistency are sought after. In this study, we introduce two new modifications to our custom-designed multizone rapid thermal CVD reactor and demonstrate their impact on growth: (1) reconfiguring the inlet gas plumbing to add a gas purifier to the helium (He) line, and (2) designing a new support wafer for consistent loading of substrates. We use statistical analysis to test the effectiveness of these modifications in improving growth and reducing variability of both CNT forest height and density. Analysis of our experimental results and hypothesis testing show that combining the implementation of He purifier with the redesigned support wafer increases forest height and reduces the variability in height (17-folds), both at statistically significant and practically significant levels.

show abstract

Carbon-assisted catalyst pretreatment enables straightforward synthesis of high-density carbon nanotube forests

Abstract: Carbonassisted catalyst pretreatment enables straightforward synthesis of high-density carbon nanotube forests. Carbon

Cited by 34 publications

References 51 publications

Synthesis of Carbon Nanotubes via Liquid Injection Chemical Vapour Deposition as a Vector for the Chemical Recycling of Waste Composite Carbon Sources

Synthesis of Carbon Nanotubes via Liquid Injection Chemical Vapour Deposition as a Vector for the Chemical Recycling of Waste Composite Carbon Sources

Synthesis of Vertical Carbon Nanotube Interconnect Structures Using CMOS-Compatible Catalysts

Reducing Variability in Chemical Vapor Deposition of Carbon Nanotubes Based on Gas Purification and Sample Support Redesign

Contact Info

Product

Resources

About