Capable of absorbing 99% of multi-frequency EM waves, improves electronics performance.

Electromagnetic waves produced by electronics can generate unwanted currents or voltages within the circuits of nearby devices, disrupting normal operation; this phenomenon is called electromagnetic interference (EMI) and can manifest as performance degradation, data corruption, or system failure, depending on the strength of the interfering frequency and the sensitivity of the electronics involved.

Electromagnetic shielding materials usually reflect this interference, sending it elsewhere to cause trouble rather than absorbing it. Materials with higher than 10% absorbance are usually limited to a single frequency band.

However, a team of scientists from the Korea Institute of Materials Science (KIMS) has developed the world's first carbon nanomaterial shielding capable of absorbing over 99% of electromagnetic waves from across multiple frequency bands simultaneously, including the big offenders: 5G/6G, WiFi, and autonomous driving radar.

Led by Byeongjin Park and Sang Bok Lee from the Composites & Convergence Materials Research Division at KIMS, the team has synthesized an ultra-thin polymer and magnetic composite film backed by crystalline structures of ferrite in patterns that absorb multiple frequencies and a carbon nanotube thin film with high shielding properties.

This structure dramatically reduces the propagation of electromagnetic waves, is less than 0.5 millimeters thick (equivalent to the thin lead in mechanical pencils), and is characterized by its uniquely low reflectance of less than 1% and high absorbance of over 99% across three different frequency bands.

"As the applications of 5G/6G communications continue to expand, the importance of electromagnetic wave absorption and shielding materials is growing," said Park. "This material has the potential to significantly improve the reliability of wireless communication devices such as smartphones and autonomous vehicle radars."

The material is thin, flexible, and durable enough to maintain its shape after 5,000 bending stress tests, making it hardy enough for application in wearable devices. It holds significant potential as an EMI shielding solution for radio frequencies being used extensively in 5G networks to provide faster service to bandwidth-intensive applications, mitigating component malfunctions across various mobile communication and radar applications.

"Further investigations are currently underway to enhance the shielding effectiveness through the development of thinner films utilizing advanced conductive patterned grid geometries," concludes the study, published in Advanced Functional Materials.

The research team has completed domestic patent registration and has applied for patents in the U.S., China, and other countries. Additionally, the technology is already being applied in several communication devices and automobiles.