Zhang Hao, Zhao Yongpeng, Yang Xuan, Zhao Guolin, Zhang Dongmei, Huang Hui, Yang Shuaitao, Wen Ningxuan, Javid Muhammad, Fan Zeng, Pan Lujun
School of Physics, Dalian University of Technology, Dalian 116024, China.
School of Microelectronics, Dalian University of Technology, Dalian 116024, China.
Nanomaterials (Basel). 2020 Oct 27;10(11):2141. doi: 10.3390/nano10112141.
Amorphous structures may play important roles in achieving highly efficient microwave absorption performance due to the polarization losses induced by the disorders, vacancies and other functional groups existed in them. Herein, a kind of amorphous TiO/rGO composite (a-TiO/rGO) was successfully fabricated via a facile one-step solvothermal method. The complex permittivity of the composites can be regulated by adjusting the addition of precursor solution. The minimum reflection loss of a-TiO/rGO composites reached -42.8 dB at 8.72 GHz with a thickness of 3.25 mm, and the widest efficient absorption bandwidth (EAB) was up to 6.2 GHz (11.8 to 18 GHz) with a thickness of only 2.15 mm, which achieved the full absorption in Ku band (12 to 18 GHz). Furthermore, the EAB was achieved ranging from 3.97 to 18 GHz by adjusting the thickness of the absorber, covering 87.7% of the whole radar frequency band. It is considered that the well-matched impedance, various polarization processes, capacitor-like structure and conductive networks all contributed to the excellent microwave absorption of a-TiO/rGO. This study provides reference on constructing amorphous structures for future microwave absorber researches and the as-prepared a-TiO/rGO composites also have great potential owing to its facile synthesis and highly efficient microwave absorption.
由于非晶结构中存在的无序、空位和其他官能团所引起的极化损耗,非晶结构在实现高效微波吸收性能方面可能发挥重要作用。在此,通过一种简便的一步溶剂热法成功制备了一种非晶TiO/rGO复合材料(a-TiO/rGO)。通过调节前驱体溶液的添加量可以调控复合材料的复介电常数。a-TiO/rGO复合材料在厚度为3.25 mm时,在8.72 GHz处的最小反射损耗达到-42.8 dB,并且在厚度仅为2.15 mm时,最宽有效吸收带宽(EAB)高达6.2 GHz(11.8至18 GHz),实现了Ku波段(12至18 GHz)的全吸收。此外,通过调节吸收体的厚度,EAB范围为3.97至18 GHz,覆盖了整个雷达频段的87.7%。据认为,良好匹配的阻抗、各种极化过程、类电容器结构和导电网络都有助于a-TiO/rGO优异的微波吸收性能。本研究为未来微波吸收体研究中构建非晶结构提供了参考,并且所制备的a-TiO/rGO复合材料因其简便的合成方法和高效的微波吸收性能也具有巨大的潜力。