A Magnetism-Assisted Chemical Vapor Deposition Method To Produce Branched or Iron-Encapsulated Carbon Nanotubes

Wei, Dacheng; Liu, Yunqi; Cao, Liqin; Fu, Lei; Li, Xianglong; Wang, Yu; Yu, Gui

doi:10.1021/ja0702465

Cited by 38 publications

(23 citation statements)

References 51 publications

(73 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[250] Wei et al reported a magnetism-assisted CVD method in which the external magnetic field promoted the coalescence or division of the magnetic catalyst particles, causing the formation of branched or encapsulated CNTs. [251] Multibranched CNT arrays can be obtained using flow fluctuation by a branching mechanism of fluctuation-promoted coalescence of catalyst particles. [252] The branched CNTs obtained can be used as intermolecular junctions components, which not only connected different CNTs for integration, but also can act as functional building blocks in circuits, for example rectifiers, field-effect transistors, switches, amplifiers, and photoelectrical devices.…”

Section: Catalysis Route Innovationmentioning

confidence: 99%

Carbon Nanotube Mass Production: Principles and Processes

et al. 2011

View full text Add to dashboard Cite

Our society requires new materials for a sustainable future, and carbon nanotubes (CNTs) are among the most important advanced materials. This Review describes the state-of-the-art of CNT synthesis, with a focus on their mass-production in industry. At the nanoscale, the production of CNTs involves the self-assembly of carbon atoms into a one-dimensional tubular structure. We describe how this synthesis can be achieved on the macroscopic scale in processes akin to the continuous tonne-scale mass production of chemical products in the modern chemical industry. Our overview includes discussions on processing methods for high-purity CNTs, and the handling of heat and mass transfer problems. Manufacturing strategies for agglomerated and aligned single-/multiwalled CNTs are used as examples of the engineering science of CNT production, which includes an understanding of their growth mechanism, agglomeration mechanism, reactor design, and process intensification. We aim to provide guidelines for the production and commercialization of CNTs. Although CNTs can now be produced on the tonne scale, knowledge of the growth mechanism at the atomic scale, the relationship between CNT structure and application, and scale-up of the production of CNTs with specific chirality are still inadequate. A multidisciplinary approach is a prerequisite for the sustainable development of the CNT industry.

show abstract

Section: Catalysis Route Innovationmentioning

confidence: 99%

Carbon Nanotube Mass Production: Principles and Processes

et al. 2011

View full text Add to dashboard Cite

show abstract

“…[185] In the pyrolysis of iron phthalocyanine, a magnet was inserted into the reaction chamber to apply a magnetic field vertical to the CNT growth direction. As the iron particles remained magnetic even in the liquid state at high temperature, a magnetic force was applied, causing the coalescence of the catalyst particles.…”

Section: D) Flow Fluctuation Cvd Methodmentioning

confidence: 99%

The Intramolecular Junctions of Carbon Nanotubes

2008

Self Cite

View full text Add to dashboard Cite

For the miniaturization of microelectronics, carbon nanotubes (CNTs) are regarded as ideal candidates for the next generation of nanoelectronics because of their excellent properties. To realize CNT‐based electronics, intramolecular junctions are required components, which can not only connect different CNTs for integration, but can also act as functional building blocks in the circuit, such as rectifiers, field‐effect transistors, switches, amplifiers, photoelectrical devices, etc. Therefore, intense attention has been focused on this topic and many advances have been achieved, especially in recent years. On the other hand, some challenges also exist. To provide researchers with a comprehensive overview of this field, this review discusses the synthesis, properties, and applications of intramolecular junctions of CNTs in detail. Among them, the applications of CNT integration are discussed specially. Furthermore, a brief summary and an outlook of future work are provided.

show abstract

“…[17][18][19][20] In our previous study, it was found that an additional magnetic field could not only make the carbon nanotubes grow along the magnetic force, but also improve the diameter uniformity and the crystallinity of graphite sheets. It has been known that a magnetic field provides an effective controllability over the growth direction, purity, yield, morphology and microstructure of carbon nanotubes (CNTs).…”

Section: Introductionmentioning

confidence: 99%

A rational design for the separation of metallic and semiconducting single-walled carbon nanotubes using a magnetic field

et al. 2016

View full text Add to dashboard Cite

The separation of metallic (m-) and semiconducting (s-) single-walled carbon nanotubes (SWNTs) without causing contamination and damage is a major challenge for SWNT-based devices. As a facile and nondestructive tool, the use of a magnetic field could be an ideal strategy to separate m-/s-SWNTs, based on the difference of magnetic susceptibilities. Here, we designed a novel magnetic field-assisted floating catalyst chemical vapor deposition system to separate m-/s-SWNTs. Briefly, m-SWNTs are attracted toward the magnetic pole, leaving s-SWNTs on the substrate. By using this strategy, s-SWNTs with a purity of 99% could be obtained, which is enough to construct high-performance transistors with a mobility of 230 cm(2) V(-1) s(-1) and an on/off ratio of 10(6). We also established a model to quantitatively calculate the percentage of m-SWNTs on the substrate and this model shows a good match with the experimental data. Furthermore, our rational design also provides a new avenue for the growth of SWNTs with specific chirality and manipulated arrangement due to the difference of magnetic susceptibilities between different diameters, chiralities, and types.

show abstract

A Magnetism-Assisted Chemical Vapor Deposition Method To Produce Branched or Iron-Encapsulated Carbon Nanotubes

Cited by 38 publications

References 51 publications

Carbon Nanotube Mass Production: Principles and Processes

Carbon Nanotube Mass Production: Principles and Processes

The Intramolecular Junctions of Carbon Nanotubes

A rational design for the separation of metallic and semiconducting single-walled carbon nanotubes using a magnetic field

Contact Info

Product

Resources

About