Lin Na, Chen Hanning, Mei Xiaokang, Chai Shitong, Lu Longsheng
School of Mechanical Engineering, Tianjin Polytechnic University, Tianjin 300387, China.
School of Computer Science and Software, Tianjin Polytechnic University, Tianjin 300387, China.
Materials (Basel). 2021 May 6;14(9):2423. doi: 10.3390/ma14092423.
The design of flexible wearable electronic devices that can shield electromagnetic waves and work in all weather conditions remains a challenge. We present in this work a low-cost technology to prepare an ultra-thin carbon fabric-graphene (CFG) composite film with outstanding electromagnetic interference shielding effectiveness (EMI SE) and electro-photo-thermal effect. The compatibility between flexible carbon fabric skeleton and brittle pure graphene matrix empowers this CFG film with adequate flexibility. The reticular fibers and porous structures play a vital role in multiple scattering and absorption of electromagnetic waves. In the frequency range of 30-1500 MHz, the CFG film can achieve a significantly high EMI SE of about 46 dB at tiny thickness (0.182 mm) and density (1.4 g cm) predominantly by absorption. At low safe voltages or only in sunlight, the film can self-heat to its saturation value rapidly in 40 s. Once the electricity or light supply is stopped, it can quickly dissipate heat in tens of seconds. A combination of the EMI SE and the prominent electro-photo-thermal effect further enables such a remarkable EMI shielding film to have more potential applications for communication devices in extreme zones.
设计出能够屏蔽电磁波且可在所有天气条件下工作的柔性可穿戴电子设备仍然是一项挑战。在这项工作中,我们展示了一种低成本技术,用于制备具有出色电磁干扰屏蔽效能(EMI SE)和电光热效应的超薄碳织物-石墨烯(CFG)复合薄膜。柔性碳织物骨架与脆性纯石墨烯基体之间的兼容性赋予了这种CFG薄膜足够的柔韧性。网状纤维和多孔结构在电磁波的多次散射和吸收中起着至关重要的作用。在30 - 1500 MHz频率范围内,CFG薄膜在微小厚度(0.182 mm)和密度(1.4 g/cm)下,主要通过吸收可实现约46 dB的显著高EMI SE。在低安全电压下或仅在阳光下,该薄膜可在40秒内迅速自热至饱和值。一旦停止供电或光照,它能在数十秒内迅速散热。EMI SE与显著的电光热效应相结合,进一步使这种卓越的EMI屏蔽薄膜在极端区域的通信设备中具有更多潜在应用。