A team of researchers from the Korea Institute of Materials Science (KIMS) has created a groundbreaking ultra-thin film that can absorb over 99% of electromagnetic waves across multiple frequencies, including those used in 5G, 6G, WiFi, and radar for autonomous driving.
This new material, developed by Dr. Byeongjin Park and Dr. Sang Bok Lee and featured as the cover article in Advanced Functional Materials, could significantly improve the reliability of wireless communication and reduce interference between electronic devices.
When electronic devices, like smartphones or WiFi routers, emit electromagnetic waves, they can interfere with nearby devices, causing them to perform poorly.
Traditional shielding materials help prevent this by reflecting electromagnetic waves, but this method has drawbacks.
These materials often reflect more than 90% of the waves, but only absorb about 10%, creating secondary interference. Plus, many materials that absorb well usually work on only one frequency band, limiting their usefulness.
The KIMS team addressed these challenges by designing a composite material that absorbs waves across multiple frequency bands and prevents them from causing interference.
The ultra-thin film, just 0.5mm thick, absorbs more than 99% of electromagnetic waves and reflects less than 1%, making it one of the most efficient shielding materials available.
This capability is ideal for improving the reliability of wireless devices, as it reduces interference better than materials that simply reflect waves.
One of the unique qualities of this film is its flexibility and durability. Even after being folded and unfolded thousands of times, the material maintains its shape and effectiveness.
This makes it a promising option for use in flexible and wearable devices, as well as rollable phones that require materials that can withstand repeated bending.
The researchers developed the material by modifying the crystal structure of ferrite, a magnetic substance, to enable selective absorption of specific frequencies.
They then created an ultra-thin polymer composite film and added a conductive pattern on the back. This pattern helps to control how electromagnetic waves move through the material, allowing it to absorb waves more efficiently at certain frequencies.
To boost shielding even further, the team applied a carbon nanotube layer on the back of the film, which has high shielding properties.
Lead researcher Byeongjin Park explained that as 5G and 6G communications continue to grow, materials that absorb electromagnetic waves will be crucial for ensuring device reliability. The research team has registered a domestic patent for their invention and filed for international patents in the U.S., China, and other countries.
They have already transferred the technology to local material companies, and it’s now being tested in actual communication devices and vehicles.
This new ultra-thin film could be a game-changer in wireless communication, making devices more dependable by reducing electromagnetic interference and paving the way for advanced technologies like autonomous vehicles and next-generation smartphones.
Source: KSR.
