Growth of Carbonaceous Nano Products and Their Application for Electromagnetic Absorption

• Main Authors: Wu, Szu-Chen, 吳思辰
• Other Authors: Liu, Yih-Ming, Ger, Ming-Der, Peng, Cheng-Hsiung
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/25101527927914843803

碩士 === 國防大學理工學院 === 材料科學與工程碩士班 === 102 === In this study, the micro-powders of magnesium oxide, nickel and Carbonyl iron were dip-coated with catalytic palladium (Pd) nano-particles to grow carbonaceous nano products (CNPs) by thermal chemical vapor deposition at different temperatures from 450℃ to 800℃. These CNP composites were used as microwave absorbing materials. The structure and morphologies of the CNP samples were examined with the X-ray diffraction (XRD) and the field-emission scanning electron microscope (FE-SEM) respectively. Raman spectrum investigation offered further information on the characteristics of the graphite structure. For microwave absorbing measurement, the CNP composites were mixed with epoxy and prepared as the microwave absorbing samples with the ratio of 20 wt% CNP composites. The complex permeability and permittivity of the samples were measured using a vector network analyzer in the frequency range of 2 to 18 GHz. The microwave absorbing effects of CNP composites grown on different substrates, magnetic and non-magnetic micro-powders, and at different temperature were evaluated. The results indicate that those CNP composites grown at lower temperature have better microwave absorbing ability because they possessed more structure defects which are beneficial for microwave absorbing. The MgO/CNPs composite grown at 600℃ have the best electromagnetic absorption capacity among all the samples prepared in this thesis.