Double-Zigzag dislocation design of porous 3D-printed carbon nanotube/sodium alginate/strontium ferrite skeletons...

Although biomass-based 3D printed skeletons with high-performance electromagnetic interference (EMI) shielding performances have garnered significant attention, it is still essential yet challenging to balance the lattice structure and EMI shielding effectiveness (SE). Herein, direct ink writing (DIW) 3D printing with assistance of Ca²⁺ crosslinking was employed to fabricate double-Zigzag dislocation carbon nanotube (CNT)/sodium alginate (SA)/strontium ferrite (SrFe₁₂O₁₉) (CSSrx/y) skeletons. Benefited from the dislocation structures composited with conductive CNT networks and magnetic SrFe₁₂O₁₉ units, the resultant CSSr18/12Ca0.2 skeleton with double-Zigzag dislocation exhibits the high average total EMI SE (SE_T) of 50.2 dB, which can prevent a Tesla coil from working properly. Moreover, an average absorption coefficient (A) of 0.59 is achieved for double-Zigzag dislocation CSSr18/12Ca0.2 skeleton, indicating the absolutely absorption-dominant shielding mechanism. Owing to the reduced edge defects and improved stress transfer, the tensile strength of double-Zigzag CSSr18/12Ca0.2 is enhanced to 6.8 MPa, which is 1.8 times that of the vertical skeleton. Double-Zigzag CSSr18/12Ca0.2 skeleton also holds superb bending resistance, anti-compressive capacity, and resultant resistance. This research provides a novel approach to design and prepare biomass-based EMI shielding materials with double-Zigzag dislocation structures, which has great application potential in the fields of electronics, aerospace, and wearable devices.