Rational construction of heterointerfaces in biomass sugarcane-derived carbon for superior electromagnetic wave absorption

The pervasive use of 5th generation mobile communication technology is driving electromagnetic wave (EW) absorbents towards high performances. The construction of heterointerfaces is crucial to the improvement of absorption ability. Herein, a series of ultralight composites with rational heterointerfaces (Co/ZnO@N-doped C/layer-stacked C, MSC) are fabricated by calcination with rational construction of sugarcane and CoZn-ZIFs. The components and structures of as-prepared composites were investigated, and their electromagnetic parameters could be adjusted by the content of CoZn-ZIFs. All the composites possess good EW absorption performances, especially for MSC-3. Its optimal minimum reflection loss and effective absorption band can reach to -42 dB and 7.28 GHz at the thickness of just 1.6 mm with 20 wt% filler loading. The excellent performances are attributed to the synergistic effect of dielectric loss stemming from the multiple heterointerfaces and magnetic loss induced by magnetic single Co. And the sugarcane-derived layer-stacked carbon and formed consecutive conductive networks and could further dissipate the electromagnetic energy through multiple reflection and conduction loss. Moreover, the simulated radar cross section (RCS) technology manifests that MSC-3 possesses outstanding EW attenuation capacity under realistic far-field conditions. This study provides a strategy for building efficient absorbents based on biomass.