Science and Technology on Thermostructural Composite Materials Laboratory, Northwestern Polytechnical University , Xi'an, Shaanxi 710072, China.
A.J. Drexel Nanomaterials Institute and Department of Materials Science and Engineering, Drexel University , Philadelphia, Pennsylvania 19104, United States.
ACS Appl Mater Interfaces. 2017 Jun 14;9(23):20038-20045. doi: 10.1021/acsami.7b04602. Epub 2017 May 31.
Microwave absorbers with layered structures that can provide abundant interfaces are highly desirable for enhancing electromagnetic absorbing capability and decreasing the thickness. The atomically thin layers of two-dimensional (2D) transition-metal carbides (MXenes) make them a convenient precursor for synthesis of other 2D and layered structures. Here, laminated carbon/TiO hybrid materials composed of well-aligned 2D carbon sheets with embedded TiO nanoparticles were synthesized and showed excellent microwave absorption. Disordered 2D carbon layers with an unusual structure were obtained by annealing multilayer TiC MXene in a CO atmosphere. The minimum reflection coefficient of laminated carbon/TiO composites reaches -36 dB, and the effective absorption bandwidth ranges from 3.6 to 18 GHz with the tunable thickness from 1.7 to 5 mm. The effective absorption bandwidth covers the whole Ku band (12.4-18 GHz) when the thickness of carbon/TiO/paraffin composite is 1.7 mm. This study is expected to pave the way to the synthesis of carbon-supported absorbing materials using a large family of 2D carbides.
具有丰富界面的层状结构的微波吸收体对于提高电磁吸收能力和降低厚度是非常理想的。二维（2D）过渡金属碳化物（MXenes）的原子层薄片使其成为合成其他 2D 和层状结构的方便前体。在这里，由嵌入 TiO 纳米粒子的二维碳片组成的层状碳/TiO 杂化材料被合成并表现出优异的微波吸收性能。通过在 CO 气氛中退火多层 TiC MXene 获得具有不寻常结构的无序 2D 碳层。层状碳/TiO 复合材料的最小反射系数达到-36 dB，有效吸收带宽范围为 3.6-18 GHz，可调厚度为 1.7-5 mm。当碳/TiO/石蜡复合材料的厚度为 1.7mm 时，有效吸收带宽覆盖整个 Ku 波段（12.4-18GHz）。这项研究有望为使用一大类 2D 碳化物合成碳负载吸收材料铺平道路。
