剥离的碳化钛（d-Ti3C2Tx）纳米片吸波性能

目的研究剥离的碳化钛(d-Ti3C2Tx)纳米片的吸波性能。方法利用HCl/LiF刻蚀,通过高速离心的方法得到d-Ti3C2Tx纳米片。利用X射线衍射仪(XRD)分析d-Ti3C2Tx的物相组成。用扫描电子显微镜(SEM)和透射电子显微镜(TEM)对d-Ti3C2Tx进行形貌分析。利用原子力显微镜(AFM)测量了d-Ti3C2Tx纳米片的厚度。利用矢量网络分析仪(VNA)测试了d-Ti3C2Tx纳米片与石蜡复合材料X波段的电磁参数。利用Cole-Cole图分析了复合材料的损耗来源,并通过电磁参数计算分析了d-Ti3C2Tx的吸波性能。结果d-Ti3C2Tx纳米片与石蜡复合材料的介电实部/虚部随着d-Ti3C2Tx浓度的增加而增大,极化的增强和电导网络的扩大是导致复合材料介电实部/虚部增加的主要原因。Cole-Cole图分析表明,复合材料中存在多种类型的极化,这分别是由缺陷、官能团和界面等引起的多重弛豫极化。吸波性能分析表明,通过改变d-Ti3C2Tx浓度,可以调控复合材料的吸波性能。当填充量达到15%时,吸波性能最佳。其在厚度为4 mm下最小反射损耗为?20.1 dB,相应的微波吸收带宽(

Microwave Absorption Properties of Delaminated Titanium Carbide (d-Ti3C2Tx) Nanosheeet

The work aims to study the microwave absorbing properties of the delaminated titanium carbide (d-Ti3C2Tx) nanosheets. Nanosheets were prepared by HCl/LiF etching and high-speed centrifugation. The phase composition of d-Ti3C2Tx was analyzed by X-ray diffraction (XRD), the morphology of d-Ti3C2Tx was analyzed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), and the thickness of d-Ti3C2Tx nanosheets was measured by atomic force microscopy (AFM). The X-band electromagnetic parameters of d-Ti3C2Tx nanosheets and paraffin composites were measured by vector network analyzer (VNA). The loss sources of the composites were analyzed by Cole-Cole diagram. The absorbing properties of d-Ti3C2Tx were analyzed by calculating the electromagnetic parameters. The dielectric real and imaginary parts of d-Ti3C2Tx nanosheets and paraffin composites increased with the increase of d-Ti3C2Tx concentration and the enhancement of polarization and the expansion of conductive network were the main reasons for the increase of real and imaginary dielectric parts of composites. Cole-Cole diagram showed that there were many kinds of polarization in composite materials, namely the multiple relaxation polarization caused by defects, functional groups and interfaces. The microwave absorption performance analysis showed that the microwave absorption performance of the composites could be tuned by changing the concentration of d-Ti3C2Tx. When the filling content reached 15%, the absorbing property was the best. The minimum reflection loss was -20.1 dB at the thickness of 4 mm, and the corresponding microwave absorption bandwidth (< -10 dB) was 1.9 GHz. d-Ti3C2Tx/paraffin composites exhibit excellent microwave absorption properties. The microwave absorption properties of d-Ti3C2Tx composites can be tuned by changing the concentration of d-Ti3C2Tx.