The effect of changing the appearance of the structure of Nano Carbon tube on its modulus of elasticity (PhD in Nano-Microelectronics)

Researcher   and author: Dr.   (   Afshin Rashid)



Note: Carbon nanotubes are hollow cylinders composed of carbon atoms in a hexagonal structure. The two common structures of zigzag and armature with various geometric and behavioral characteristics are studied in order to evaluate the effect of the type of structure on changes in mechanical properties, the most important of which is the modulus of elasticity. 

These two widely used structures in the present study have been modeled by finite element method in Mark analyst software and the effect of changing the appearance of the carbon nanotube structure on its modulus of elasticity has been studied. The behavior of covalent bonds between carbon atoms is assumed by assuming bending elements with modulus of elasticity and a certain Poisson's ratio and applying a net tensile load to its upper surface to calculate the amount of modulus of elasticity of the structures under study. According to studies, the armature structure has a higher modulus of elasticity compared to zigzag specimens.



Zigzag specimens always tend to increase their modulus of elasticity and reach the corresponding value corresponding to the ideal structure of the armature. The direction of rolling up (rolling or  chiral  vector) of graphene layers determines the change in electrical properties of nanotubes. Chirality describes the hexagonal lattice angle of a carbon nanotube. Nano seat tubes   - so-called because of the shape of the seat like their edges - have the same chiral characteristics and are highly desirable for their complete guidance. They are not unlike  zigzag nanotubes   , which may be semiconductors. Converting a 30-degree graphene sheet changes the nanotube that changes from chair to chair or zigzag or vice versa.While MWCNTs always reach and reach at least the same level of conductivity of metals, the conductivity of SWCNTs depends on their chiral vector. The properties of carbon nanotubes are not the same.At present, SWCNTs are prepared by various techniques such as arc discharge, hydrocarbon pyrolysis in the presence of catalyst, laser evaporation and chemical vapor deposition. , Spring-like and spiral. Existence of different structures expands the properties and applications of SWCNTs, but newly synthesized SWCNTs contain many different nanotubes, which is the main obstacle to their use in high-efficiency nano-equipment. It has been shown that the physical and electronic properties of a SWNT depend on the diameter of the tube and its structure (m, n). In most applications, we need nanotubes with the same properties. Example The performance of a CNT-based nanoelectronic device is significantly improved by using the same nanotubes. Field effect transistors with on / off ratios of 106, using carbon nanotubes enriched with (5,



Conclusion: 

 Carbon nanotubes are hollow cylinders composed of carbon atoms in a hexagonal structure. The two common structures of zigzag and armature with various geometric and behavioral characteristics are studied in order to evaluate the effect of the type of structure on changes in mechanical properties, the most important of which is the modulus of elasticity. 

Researcher   and author: Dr.   (   Afshin Rashid)

PhD in Nano-Microelectronics