Bioinspired Carbon Superstructures for Efficient Electromagnetic Shielding

Biologically inspired superstructural materials exhibit wide application prospects in many fields, in terms of mitigating increasingly serious electromagnetic (EM) pollution in the civil field. Here, we successfully obtain bamboo slices with uniform pore size distribution through the advanced bamboo transverse splitting technology developed by our group previously and prepare large-scale honeycomb-like carbon-based tubular array (CTA) structures with a controllable pore size, graphitization degree, and selectable conductivity property. Based on the simulation and experimental results, the EM shielding performance of CTAs is proven to be sensitive to the microchannel aperture size and the EM energy incident angle, which is attributed to the difference in the propagation rate of induced electrons in different directions. Among the candidates, CTA-middle-1500 exhibits the best shielding performance against incident EM energy with average SE/ρ values of 123.7 and 144.5 dB cm3 g-1 for perpendicular and parallel directions, respectively, showing its application potential as a lightweight and efficient EM shielding material. The predicted optimal incident angle for CTA-middle-1500 against EM energy radiation is 15°, with the largest RCS reduction value of 26.1 dB m2. The excellent EM shielding performance is attributed to the good reflection capacity involved with the high conductivities of the CTAs.