碳纳米管的本征微波吸收特性研究

从碳纳米管电磁参数和微波吸收特性的实验结果出发,分析探讨了碳纳米管的本征微波吸收机理,并得出结论:界面极化吸收、多重反射和散射以及螺旋型碳纳米管的手性微波吸收是碳纳米管的主要本征微波吸收机理.碳纳米管的结构缺陷能增强极化效应,从而增加介电损耗;碳纳米管所具有的小尺寸效应、表面效应(比表面积大)、量子尺寸效应和宏观量子隧道效应等有利于其微波吸收.碳纳米管的电容率值远大于磁导率值,碳纳米管是一种介电损耗型吸波介质.

Investigation of the Microwave Absorbing Properties of Intrinsic CNTs

Based on the experimental data for both the electromagnetic parameters and the microwave absorbing properties of CNTs,the microwave absorbing mechanisms of intrinsic CNTs are investigated and revealed systematically.The following conclusions are obtained.The interfacial polarization absorption,the multiplicate reflection and scatter of microwave in the pore structures of CNTs as well as the chiral microwave absorption of helical CNTs are the main microwave absorbing mechanisms of intrinsic CNTs.In addition,the structural defects of CNTs can enhance charge polarization,which will cause more dielectric loss.CNTs have a series of novel physical effects,such as small size effect,effect of large specific surface area,quanta-size effect and tunneling effect,contributing to microwave absorption.The complex permittivity of CNTs is large,but their microwave permeability is comparatively small.Intrinsic CNTs are dielectric loss wave-absorbed material.