Investigation On Microwave Absorbing Mechanisms Of Hydrogen Plasma In Carbon Nanotubes

Carbon nanotubes (CNTs) are ideal quasi-one-dimensional nano-materials. witha novel structure, singular physical properties and chemical properties, Having uniqueelectromagnetic properties. At present, the microwave absorbing and attenuationproperties of Hydrogen Plasma in CNTs is one of the focus research areas in materialsscience. having broad application prospects in both military stealth and civilianmicrowave radiation protection.First of all, structures characteristics of carbon nanotube, basic properties, andwave-absorbing mechanism of materials are reviewed on the system in this paper.Based on the Introduction experimental data of CNTs by iron-catalyzedhigh-pressure disproportionation (HiPco) exhibit the strong microwave(around2.45GHz) absorption. observed by some groups such as Wadhavan et al., Imholt et al., andNaab et al., Using double-fluid theory and phenomenological model, We researchmicrowave absorption and attenuation properties of hydrogen plasma in HiPco CNTsby only considering electron collision absorption, and both considering electroncollision absorption and ion collision absorption in this paper. Revealed mechanism ofmicrowave absorption of hydrogen plasma in HiPco CNTs. According toAppleton–Hartee formula, and W.K.B approximation, We study in deeply the additionof static magnetic field and directions influence on microwave loss absorption ofhydrogen plasma in CNTs. The complex dielectric constant, the microwave waveabsorption coefficient formula by a complex refractive index and the attenuationcoefficient formula of the incident electromagnetic wave of a variety of cases underdifferent condition, are respectively deduced theoretically. Then a microwaveabsorption model of hydrogen plasma in CNTs is developed.The theoretically simulation results are in quantitative agreement with theexperimental data,which well explained experimental phenomena by Wadhavan,Anand and Naab observed. It is proved that microwave energy loss is predominantly caused by the collisional absorption of the charge particle in hydrogen plasma inHiPco CNTs. The results show that as long as electron Effective collision frequency,liberal electron density, the angle between Electromagnetic wave propagationdirection and the addition of static magnetic fields, and Magnetic field strength inhydrogen plasma in CNTs is modestly controlled, strong microwave absorption forspecified frequency range can be obtained.Research object of this paper is proposed theoretical guidance of application ofmicrowave absorption in military stealth and civilian microwave radiation protection.