Flexible Single-Walled Carbon Nanotube Film with Ultrahigh Absolute Electromagnetic Shielding Performance

The rapid development of wearable electronic devices and fifth-generation (5G) communications have stimulated an urgent demand for flexible electromagnetic interference (EMI) shielding materials. Conventional metal-based EMI shielding materials typically fail to concurrently achieve good flexibility and effective EMI shielding performance. In this study, we prepared single-walled carbon nanotube (SWCNT) films comprising high-purity, high-crystallinity and high-aspect-ratio SWCNTs by floating catalyst chemical vapor deposition (FCCVD) followed by gas-phase purification. The obtained SWCNT film showed good flexibility, low density, and high electrical conductivity. A record-high absolute EMI shielding effectiveness (EMI SSE/t) of 5.42 × 105 dB·cm2/g and an exceptional normalized EMI shielding effectiveness (EMI SE/t) of 2.93 × 105 dB/cm, about twice as high as the highest reported EMI SSE/t value, were achieved for our SWCNT films. These results demonstrate that SWCNT films can be an ideal flexible EMI shielding material for use in next-generation wearable electronics and 5G communication systems.