Investigation on physical properties of carbon nanotubes prepared by mechanothermal method

Carbon nanotubes (CNTs) have specific physical properties that make them one of the ideal nano-materials for electronics, magnetic, and optical applications. Produced CNTs via mechanothermal method have a springy and coil-like structure, affecting their physical characteristics and distinguishes them from other carbon nanotubes. In this research study, the optical and magnetic properties of fabricated carbon nanotubes by mechanothermal method were investigated. For this purpose, carbon nanotubes were synthesized by heat treatment of ball-milled graphite powders at 1400 ˚C in the atmosphere of argon. The quality and structure of milled-graphite and the CNTs were investigated using X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM) and Raman spectroscopy. Then, the optical and magnetic properties of the fabricated CNTs were assessed by UV-VIS spectrometer and vibrating-sample magnetometer (VSM), respectively. The results of the absorption spectra revealed that the products had not any absorption peak at the visible regime. Furthermore, magnetization curves indicate that coercivity (Hci), magnetization (Ms), and retentivity (Mr) of the CNTs were found to be 84.183 G, 20.531, and 0.73511 emu/g, respectively.