【摘要】 通过湿化学技术法制备了La2O3∶Eu3+纳米晶充填碳纳米管复合材料。高分辨透射电镜观测到充填碳纳米管的La2O3∶Eu3+纳米晶在碳纳米管内呈准连续状态分布。HP8722ES矢量网络分析仪测量了样品在2~18GHz频率范围内的复介电常数和复磁导率。材料反射率损耗(R.L.)、匹配频段(fm)及匹配厚度(dm)采用吸收屏理论公式计算。结果表明,样品反射率随吸收层匹配厚度的增大,吸收峰向低频方向迁移并有窄化的趋势。吸收层在X波段具有较好的吸波效果。当吸收层匹配厚度为dm=9.0mm时,在10.6~12.8GHz频段内,反射衰减最大达-25.64dB,反射衰减<-5dB的频宽达2.21GHz。更多还原

【Abstract】 The preparation and characterization of La2O3∶Eu3+ filled CNTs composites were studied for microwave absorption applications in the range of 2 to 18GHz.The samples were characterized by transmission electron microscopy.The complex relative permittivity and permeability of the absorber were measured in a frequency range of 2 to 18GHz.The reflection loss(R.L.),matching frequency(fm) and matching thickness(dm) were calculated using the theory of the absorbing wall.The electromagnetic properties and microwave-absorbing characteristics effects by the encapsulated La2O3∶Eu3+ in the carbon nanotubes were investigated.A matching thickness is found corresponding to a matching frequency.The maximum reflection loss is about-25.64dB and the bandwidth corresponding to the reflection loss below-5dB is more than 2.21GHz.With increasing thickness,the maximum reflection coefficient shifts to lower frequency.更多还原