Single Wall CNT

Single Wall CNT List

Single wall CNTs are nanomaterials. When the scale of a material is reduced to the nanometer scale, it will produce especially excellent properties and effect, including self-assembly effect, small size effect, surface effect and quantum effect. The single wall CNT is consisted of only one cylindrical surface that made of carbon atoms. The walls of the single wall CNT are made up of hexagonal grids that similar to graphite sheets. Carbon atoms are located in the intersection of hexagonal grids and every carbon atom is adjacent to other three surrounding carbon atoms. The diameter of single wall CNT can be determined by Raman spectroscopy, most of which are between 1.16 nm and 1.60 nm. In the single wall CNT, the motion of electrons in the radial direction is limited, but the motion of electrons along the axial direction is not limited. Therefore, single wall CNT can be considered as a one-dimensional quantum wire. In addition, because of the surface effect, single wall CNT generally has a large specific surface area.

Figure 1. The structure of single wall CNT.

Applications:

• Large capacity supercapacitors field: Large capacity supercapacitors play an important role in the preparation of electronic devices. For a double layer supercapacitor, the amount of stored energy is determined by the effective specific surface area of the capacitor electrode plate. Single wall CNT has the advantages of large specific surface area and good electrical conductivity, and can be used to prepare capacitor electrodes, which can significantly improve the capacity of double-layer supercapacitors.

Figure 2. The ink based on single walled carbon nanotube for supercapacitors.

• Hydrogen storage material field: With the shortage of resources and prominent environmental pollution problems, developing new clean energy sources has become the research hot point. As a clean energy, hydrogen will play an important role in the future energy. Hydrogen is an ideal next-generation energy source with high energy content, no environmental pollution and abundant resources. However, hydrogen storage and transportation are the key links in the practical application of hydrogen energy. With the advantages of large specific surface area, single wall CNT has a good adsorption effect on hydrogen. Therefore, single wall CNT are very suitable to be used as hydrogen storage materials, which plays a great role in promoting the practical application of hydrogen energy.
• Composite materials Field: Single wall CNTs have unique and perfect structure and very large aspect ratio, which makes them have extraordinary mechanical properties and suitable for composite reinforcement. As composite reinforcing materials, single wall CNTs can be prepared into a variety of composite materials, including CNTs/iron matrix composites, CNTs/aluminum matrix composites, CNTs/nickel matrix composites, CNTs/copper matrix composites and the others.
• The others: Single wall CNTs are also widely used in other fields, including transistors, catalysis, biomedicine and the others.

Classification:

According to the solubility, single wall CNTs can be divided into water-soluble single wall CNTs and water-insoluble single wall CNTs.

• Water-soluble single wall CNTs: Water-soluble single wall CNTs have good dispersion and solubility in aqueous solution and can be widely used in biomedical field.
• Water-insoluble single wall CNTs: The dispersibility and solubility of water-insoluble single wall CNTs in aqueous phase are very poor, which mostly is applied in oil situation.

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. Guo S, Wang W, Ozkan C S, et al. Assembled graphene oxide and single-walled carbon nanotube ink for stable supercapacitors[J]. Journal of Materials Research, 2013, 28(7):918-926.