Ti3C2Tx MXene‐Based Superhydrophobic Broadband Terahertz Absorber with Large Pore‐Size Foam Architecture.

Porous polymer‐based Terahertz (THz) absorbers possess strong absorption with broadband, lightweight, and flexible features. Thus these are widely desired in THz electromagnetic shielding, radar‐cross‐section reduction, radiometer calibration, etc. However, the harsh environment of humidity, corrosiveness, and dustiness undermines the performance and service lifetime of the porous absorbers. Here, based on Ti3C2Tx MXene sponge composite foam (MSF), a superhydrophobic broadband THz absorber on a large pore‐size porous architecture by a joint hydrophobic strategy is realized. Results show that the apparent contact angles and roll‐off angles of the modified MSF reached 159.0° and 7.6°, while maintaining an ultra‐high absorption rate of 99.6% in the frequency range of 0.3–1.2 THz. Furthermore, the special Micro‐Nano hierarchical structures render the absorber a strong bounce‐off ability to the droplets of an aqueous solution. These water‐repellent properties endow the absorber the versatility of self‐cleaning and anti‐corrosion, thus can be widely applied in many scenarios including THz remote sensing, communication, and security screening as well. [ABSTRACT FROM AUTHOR]