Effect of Electron Beam and Gamma Rays on Carbon Nanotube Yarn Structure

Abstract

Individual carbon nanotubes (CNTs) exhibit excellent mechanical, electrical and thermal properties, leading to development of a new generation of advanced lightweight materials and spacecraft electronics substituting the electronics based on silicon. The direct assembly of CNTs into macroscopic fibers or sheets has been a way to overcome their dispersion and processing challenges. Because of a wide range of applications of this material, we investigate effectively the defects on CNT yarns structures created by electron beam and gamma sources and their impact on the morphology and mechanical properties. The irradiated samples with electron beam at doses of 400, 600 and 800 kGy had a decrease in the strength from 219.60 ± 18.90 MPa for pristine yarn to 108. 86 ± 23.77, 153.15 ± 21.63, 170.50 ± 25.78 MPa, respectively. The sample irradiated with gamma in air at dose of 100 kGy had the strength increased slightly as compared with the pristine sample and an increase in the elasticity modulus from 8.79 ± 1.19 to 19.63 ± 2.02 GPa as compared to CNT pristine yarn. The quality of the CNT yarns that was gamma irradiated in air with absorbed dose of 100 kGy was not affected by the radiation process with improvement of 123% of the Young's modulus.

Carbon nanotube yarns derived from gamma irradiated carbon nanotube forests

“…10,11,17,19 In addition, it was also reported that γ-irradiation of CNTs resulted in a reduced tube diameter and reduced empty inter-wall spaces. 10,19,20…”

Effects of electron beam irradiation on characteristic properties of expanded graphite

“…These results indicate that after electron beam irradiation or after thermal shock, the structure of graphite has been self-assembled better than that of the untreated samples; moreover, the combination of EB irradiation and then thermal shock of graphite samples were obtained in the sample EG10-120 with less defect structure than EG0. In addition, the 2D peak position of the sample is shifted to the position with a lower wave number than G0, indicating a decrease in the number of layers or expansion in the graphite structure after irradiation or heat shock [5,13,[15][16][17].…”

“…Expansion graphite has been studied and fabricated by many different methods such as using chemical agents inserting graphite structure and then thermal shock at high temperature [6,[11][12][13] or by microwave [4,14]. In addition, direct treatment of graphite by ionizing radiation (gamma rays, electron beams...) to change the structure was also studied [15][16][17][18].…”

Clustering Artificial Atoms Induced by High-Frequency Electromagnetic Radiation in Graphene Monolayers of Multiwalled Carbon Nanotubes

“…Subsequently a fast surface diffusion of knocked-out C atoms proceeds very fast in the vacancies places (vacancy annealing) [4]. The atoms, which are knocked out of the graphene plane or ultrathin crystal under action of high-energy (1 MeV-1 GeV) ions [5][6][7], electrons (see [6,[8][9][10] and references therein), protons and positrons (see [6,11] and references therein), cannot escape from the graphene plane to enter the deep bulk region. Emerging in beta-rays-,ions-irradiated graphene the radiation vacancies form clusters.…”

“…Emerging in beta-rays-,ions-irradiated graphene the radiation vacancies form clusters. [8,12,13] The vacancies are neutral, but they host a positively charge by applying electromagnetic pulses [13].…”