Biomass-Derived Crocodile Skin-Like Porous Carbon for High-Performance Microwave Absorption

Biomass-derived porous carbon materials have received extensive attention in electromagnetic wave absorbing (EMA) materials due to their stability, lightweight, and friendliness. Adjusting the morphology of porous carbon materials is an effective way to improve their absorbing properties. In this work, the crocodile skin-like biomass hierarchical porous carbon (BHPC) material was synthesized from waste rice husk via a carbonization and alkali activation process. The effect of the consistency of the activator on the porous morphology is investigated. Under ultra-low filler content of 10 wt%, the minimum reflection loss (RLmin) of the BHPC-10 composite material reaches -47.46 dB, and the effective absorption bandwidth (EAB) is up to 3.40 GHz in the X-band at a thickness of 2.8 mm. This work provides a reference for preparing porous carbon materials derived from pure biomass and a feasible scheme for designing high-performance microwave absorbing materials.