A team of scientists from the Korea Institute of Materials Science (KIMS) has achieved a groundbreaking feat by developing the world’s first ultra-thin composite material capable of absorbing more than 99% of electromagnetic waves across multiple frequency bands, including 5G/6G, WiFi, and autonomous vehicle radar. This innovative material, less than 0.5mm thick, offers an extraordinary combination of low reflectance (less than 1%) and high absorbance (over 99%) across three critical frequency bands.
Electromagnetic waves emitted by electronic components can cause significant interference, degrading the performance of nearby devices. Electromagnetic shielding materials are typically used to prevent this interference, but traditional shielding methods are often not efficient enough. Conventional materials tend to reflect over 90% of electromagnetic waves, with actual absorbance levels often as low as 10%. Additionally, most materials with higher absorbance are limited to absorbing waves in a single frequency band, making them unsuitable for multi-functional applications.
To overcome these limitations, the KIMS team, led by Dr. Byeongjin Park and Dr. Sang Bok Lee, developed a composite material capable of absorbing electromagnetic waves from multiple frequency bands simultaneously. This technology not only absorbs electromagnetic waves but also effectively eliminates secondary interference, ensuring that nearby electronic devices operate more reliably.
The material is exceptionally thin, flexible, and durable, allowing it to retain its shape even after being folded and unfolded thousands of times. These characteristics make it ideal for applications in devices like rollable phones and wearable technology.
The team’s success stems from their innovative approach to designing the material. They synthesized a magnetic material by altering the crystal structure of ferrite, enabling it to selectively absorb electromagnetic waves at specific frequencies. The ultra-thin polymer composite film they produced incorporates conductive patterns on its back side to control the propagation of electromagnetic waves. By adjusting these patterns, they significantly reduced reflection at specific frequencies, thus enhancing absorption. Additionally, a carbon nanotube thin film was applied to the back of the composite to further improve the material’s electromagnetic shielding properties.
Dr. Byeongjin Park, Senior Researcher at KIMS, emphasized the growing importance of electromagnetic wave absorption and shielding as the use of 5G/6G communication technologies expands. He highlighted the potential of this new material to significantly improve the performance and reliability of wireless communication devices, including smartphones and autonomous vehicle radar systems.
The research, titled “Absorption-Dominant Electromagnetic Interference (EMI) Shielding across Multiple mmWave Bands Using Conductive Patterned Magnetic Composite and Double-Walled Carbon Nanotube Film”, was published as the cover article in the October 1st edition of Advanced Functional Materials. The findings were supported by KIMS’ fundamental research projects and the Electromagnetic Solution Integrated Research Group (SEIF) under the National Research Council of Science & Technology.
The research team has already secured domestic patents and filed applications for patents in the U.S., China, and other countries. The technology has been transferred to several domestic material companies and is currently being applied in real-world communication devices and automobiles, indicating its promising commercial potential.
This revolutionary electromagnetic wave absorption material marks a significant leap forward in materials science and has the potential to transform industries reliant on wireless communication and electronic devices.
By Impact Lab
