Hair-thin film blocks over 99.9999999% of radar-band electromagnetic waves

Researchers in South Korea have developed a new film composed of carbon nanotube fibers and MXene, which blocks over 99.9999999% of radar-band electromagnetic waves. This material, only 17.5 micrometers thick, is five times thinner than a human hair but exhibits tensile strength comparable to high-strength steel. It combines the lightness and toughness of carbon nanotube fibers with the conductivity and low infrared radiation of MXene, making it suitable for military and aerospace applications where electronic protection is crucial.

The film's construction involves aligning carbon nanotube fibers as 'bricks' and using MXene as 'mortar' to fill the spaces. This method prevents the fibers from slipping and creates a conductive network. Taehoon Kim of the Korea Institute of Materials Science highlighted the importance of combining materials with complementary properties to enhance performance.

In tests, the film achieved around 90 decibels of electromagnetic shielding across radar and communication frequency bands, including some 5G and 6G systems. Although it effectively blocks electromagnetic waves, it does not provide radar invisibility, as it was not tested for reducing reflected signals.

Additionally, the MXene coating reduces infrared radiation, making the film less detectable by thermal cameras. This effect persists from room temperature up to 300 degrees Celsius. The film's durability was demonstrated through repeated bending and exposure to harsh conditions.

While the film remains a laboratory material, its potential applications extend beyond defense systems to include next-generation communication devices and wearable electronics. The research was published in the journal Advanced Composites and Hybrid Materials.