Zhao Tingkai, Hou Cuilin, Zhang Hongyan, Zhu Ruoxing, She Shengfei, Wang Jungao, Li Tiehu, Liu Zhifu, Wei Bingqing
School of Materials Science and Engineering, Northwestern Polytechnical University, Xi'an 710072, P. R. China.
Department of Materials Science and Engineering, Northwestern University, Evanston IL 60208, USA.
Sci Rep. 2014 Jul 10;4:5619. doi: 10.1038/srep05619.
Amorphous carbon nanotubes (ACNTs) with diameters in the range of 7-50 nm were used as absorber materials for electromagnetic waves. The electromagnetic wave absorbing composite films were prepared by a dip-coating method using a uniform mixture of rare earth lanthanum nitrate doped ACNTs and polyvinyl chloride (PVC). The microstructures of ACNTs and ACNT/PVC composites were characterized using transmission electron microscope and X-ray diffraction, and their electromagnetic wave absorbing properties were measured using a vector-network analyzer. The experimental results indicated that the electromagnetic wave absorbing properties of ACNTs are superior to multi-walled CNTs, and greatly improved by doping 6 wt% lanthanum nitrate. The reflection loss (R) value of a lanthanum nitrate doped ACNT/PVC composite was -25.02 dB at 14.44 GHz, and the frequency bandwidth corresponding to the reflector loss at -10 dB was up to 5.8 GHz within the frequency range of 2-18 GHz.
直径在7 - 50纳米范围内的非晶态碳纳米管（ACNTs）被用作电磁波的吸收材料。通过浸涂法，使用稀土硝酸镧掺杂的ACNTs与聚氯乙烯（PVC）的均匀混合物制备了电磁波吸收复合薄膜。利用透射电子显微镜和X射线衍射对ACNTs和ACNT/PVC复合材料的微观结构进行了表征，并使用矢量网络分析仪测量了它们的电磁波吸收性能。实验结果表明，ACNTs的电磁波吸收性能优于多壁碳纳米管，并且通过掺杂6 wt%的硝酸镧得到了极大改善。硝酸镧掺杂的ACNT/PVC复合材料在14.44 GHz时的反射损耗（R）值为 - 25.02 dB，在2 - 18 GHz频率范围内，对应于 - 10 dB反射器损耗的频率带宽高达5.8 GHz。
