MXene/Carbon Nanotube Composite Yarn for Energy Storage and Electromagnetic Interference Shielding

MXene or MXene-based composite fibers hold the potential to power wearable smart garments as flexible capacitors. However, pure MXene suffers from extremely poor mechanical properties, while MXene composite fibers exhibit low specific capacitance, limiting their practicality for wearable smart clothing applications. To overcome the challenge of low specific capacitance in MXene composite fibers, Carbon Nanotube (CNT)yarn served as an important substrate, which was coated with MXene to obtain MXene/CNT yarn supercapacitor (YSC) exhibiting excellent electromagnetic Interference(EMI) Shielding performance. Utilizing the synergistic effect between MXene and CNT yarn, the resulting composite achieved a conductivity of 1263.82 S/cm at an MXene loading of 0.41 mg/cm. The thermodynamics and kinetics of the coating process were investigated. The MXene/CNT YSC achieved a specific capacitance of 70.25 F cm−1 at 20 mV s−1 and 183 F cm−3 at 0.1 A cm−3, with a capacitance retention of ≈86% after 12,000 galvanostatic charge-discharge (GCD) cycles at 0.1 A cm−3. A fully woven MXene/CNT fabric exhibited an EMI shielding effectiveness of 35 dB at a thickness of 0.45 mm. Our work provides a new strategy for fabricating energy-storage yarns with outstanding EMI shielding performance.