材料科学
反射损耗
微波食品加热
多孔性
复合材料
电介质
吸收(声学)
导电体
介电损耗
电导率
极化(电化学)
反射(计算机编程)
复合数
光电子学
化学
物理
物理化学
量子力学
程序设计语言
计算机科学
作者
Kexuan Hu,Hehe Wang,Xiang Zhang,Hui Huang,Tai Qiu,Yang Wang,Chuanfang Zhang,Limei Pan,Jian Yang
标识
DOI:10.1016/j.cej.2020.127283
摘要
Light weight is one significant pursuit for microwave absorption (MA) materials. Generally, constructing foams with porous structure and low density as the absorber is one efficient way to reduce the absorber content and the quality of MA materials since the porous structure can effectively cause multiple reflections of electromagnetic waves and enhance the MA performance. Herein, we report a new and simple method for fabricating ultralight Ti3C2Tx foams by hydrochloric acid induced self-assembly and freeze-drying, for which the pore structure and MA performance can be effectively regulated by pre-freezing temperature. The decrease of pre-freezing temperature from −20 °C to −196 °C results in a reduced pore size, more homogenous pore structure, a decreased electrical conductivity, a decreased dielectric constant and a significantly enhanced MA performance. 3.3 wt% Ti3C2Tx foams was immersed into molten paraffin to prepare composites for the MA performance tests. Due to the synergy of multiple reflection, conductive loss and polarization relaxation, the Ti3C2Tx foams pre-frozen at −196 °C shows the most superb and impressive MA performance, a minimum reflection loss (RL) of −50.6 dB at the thickness of 1.8 mm and an effective absorption bandwidth (EAB) of 4.2 GHz (13.8–17.6 GHz) at the thickness of 1.4 mm, and the EAB could be adjusted in a range of 11.9 GHz (6.1–18 GHz) by increasing the thickness from 1 mm to 3 mm. This is one of the most lightweight materials with excellent MA performance to our knowledge, which perfectly meet the combined pursuit of light weight, thin thickness, broad bandwidth and strong absorption. This work offers a simple strategy for constructing 3D porous Ti3C2Tx-based foams facing the application such as MA, electromagnetic shielding, environmental governance, energy storage and sensors.
科研通智能强力驱动
Strongly Powered by AbleSci AI