A high-performance eletromagnetic wave absorption material based on biochar derived from pomelo peel

As a kind of renewable resources with abundant reserves, research on the utilization of biochar has been paid more and more attention. However, the use of pomelo peel biomass carbon in the field of eletromagnetic wave absorption (EWA) has never been reported. In this study, the pomelo peel of natural recovery were carbonized at temperature of 700°C for 1 h in a high vacuum of 300 pa. The as-prepared biomass carbon were uniformly mixed with the paraffin by heat-assisted impregnation to prepare small ring-shaped devices, and the EWA characteristics of the small devices were investigated. The absorbing measurements were performed with the filling mass fraction of 30% and 50% of the biochar, respectively. The biochar with a mass fraction of 50% showed the excellent absorbing properties with the maximum reflection loss up to –44.3 dB at 9.84 GHz in the thickness of 2.0 mm, which is expected to be used as light, broadband and efficient EWA material.