3D printing of customizable and lightweight multilayer MXene/nanocellulose architectures for tunable electromagnetic interference shielding via direct ink writing

To cope with the miniaturization trend of electronic equipment, future electromagnetic interference shielding (EMI) materials need to meet the customization and flexibility on a three-dimensional (3D) scale. However, it is still a challenge for conventional manufacturing strategies to customize and design structures. Herein, we demonstrate a simple physical grinding of multilayer-MXene (m-Ti3C2Tx)/cellulose nanofibrils (CNFs) inks to print lightweight and well-conductive scaffolds by direct ink writing (DIW). The formed 3D conductive scaffolds with macro and micro pore scales exhibit an optimal EMI shielding effectiveness of about 110 dB in the X-band with a low bulk density of 139.3 mg cm(-3), outperforming many reported EMI shielding materials. Meanwhile, by adjusting the ink composition, printed layer numbers, and filament spacing, it obtains a hierarchical architecture with a wide range of tunable EMI values of 6.8-110 dB. The EMI shielding effectiveness of the scaffold can reach more than 45 dB in the ultra-broadband gigahertz band (8.2-40 GHz). More importantly, a variety of printed shields matched with electronic components are constructed via DIW to simulate practical applications (Bluetooth module, Tesla coil). This work with an easy-to-manufacture approach and excellent performance provides great potential for miniaturized portable devices and GHz applications.