Multi Wall CNT

Multi Wall CNT List

As a new carbon allotrope, carbon nanotubes have attracted wide attention and brought great commercial value since they were discovered. The stable existence of carbon nanotubes can be divided into two categories, which is single wall CNTs and multi wall CNTs. Among them, multi wall CNTs are important nanomaterials and have been widely used in many fields. With the advantages of light weight, perfect hexagon structure connection and nanoscale size, multi wall CNT has been a research hotspot in the field of nanotechnology. In terms of structure, the multi wall CNT can be regarded as seamless and hollow tubular materials coiled into multi-layered concentric graphene sheets formed by carbon atoms. With the rapid development of science and technology, great progress has been made in the study of multi wall CNTs, including the preparation process, the modification method and the others.

Figure 1. The structure of multi wall CNT.

Applications:

• Adsorbent field: Multi wall CNTs are one-dimensional quantum materials with high specific surface area, high specific surface energy and high reactivity. Due to the unique surface structure , multi wall CNTs have excellent adsorb ability to both liquid and gas. Therefore, multi wall CNTs have been widely used in the field of adsorbent. For example, with the rapid development of economy and industry, oil is being used more and more. Due to the imperfection of various management systems and the backwardness of treatment technology, a large amount of oil products flow into water bodies, forming serious pollution. As adsorbent, multi wall CNTs exhibit good adsorption and recycling performance for petroleum organic compounds, which can effectively alleviate oil pollution.
• Catalytic field: With the characteristics of nanoscale tube structure, large aspect ratio, large specific surface area and big surface binding energy, multi wall CNTs can absorb substances and be filled with particles, which has a good application prospect as catalyst carriers. Multi wall CNTs supported catalysts can improve the specific surface area of active components to the greatest extent, which not only solves the problem of small specific surface area and low catalytic activity of conventional catalysts, but also eliminates the problem of agglomeration of pure nanoscale catalyst powders. Therefore, multi wall CNTs have a broad application prospect in the field of catalysis.

Figure 2. An example of multi wall CNTs applied in catalytic field.

• The others: Multi wall CNTs also have important applications in other fields, such as sensors, energy storage, biology, medicine and the others.

Classification:

According to the dispersion and solubility of multi wall CNTs in various solvents, they can be divided into water-soluble multi wall CNTs and non-water-soluble multi wall CNTs.

• Water-soluble multi wall CNTs: Water-soluble multi wall CNTs have good dispersibility and solubility in aqueous solution. It is usually necessary to modify multi wall CNTs by covalent and non-covalent methods to obtain water-soluble multi wall CNTs.
• Non-water-soluble multi wall CNTs: Non-water-soluble multi wall CNTs have poor dispersibility and solubility in aqueous solution and are generally not suitable for biomedical applications.

References

1. Rafique I, Kausar A, Anwar Z, et al. Exploration of Epoxy Resins, Hardening Systems, and Epoxy/Carbon Nanotube Composite Designed for High Performance Materials: A Review[J]. Polymer-Plastics Technology and Engineering, 2016, 55(3):312-333.
2. Yanxia L, Cheng J, Shengheng L, et al. Intrinsic Catalytic Activity of Gold/Multi-Walled Carbon Nanotubes Composites in Squaric Acid-Iron(II/III) System[J]. Catalysts, 2018, 8(5):187.