Activated carbon derived from mango leaves as an enhanced microwave absorbing material

Abstract

Microwave absorbing materials have become an important component in electronics, communication, and modern warfare. The present study reports porous activated carbon derived from mango leaves biomass and by facile method of carbonization and activation. The porous activated carbon has the potential to become an efficient microwave absorbing material. The SEM and FESEM images clearly showed the porous structure which was further confirmed using BET analysis. The sample having 20 wt% loading of activated carbon in paraffin wax gave the Highest Reflection Loss (RLmax) of −23.26 dB at 17.68 GHz & 1.50 mm thickness. The maximum effective absorption band width (i.e. reflection loss < −10 dB) of 5.17 GHz was obtained at 1.75 mm thickness, which covered 86.16% of Ku band. The effective absorption bandwidth of 3.31 GHz was also obtained at 2.5 mm thickness which covered 82.75% of X band. This excellent microwave absorption property was obtained by high impedance matching and subsequent attenuation of microwave by dielectric loss facilitated by the porous structure. This work provides a new source of biomass which is abundant in nature and can be easily processed as an enhanced microwave absorbing material having large effective absorption bandwidth at less thickness and low filler loading.