Chips/graphene conductive boards with excellent electromagnetic shielding properties

Woodchips have attracted attention as wood derivatives because their chemical composition is similar to that of wood but can be manipulated to remove their anisotropic properties. We exposed the cellulose inside woodchips through chemical treatments and used the interaction between chips, graphene, and Ca2+ to process them into new electromagnetic-shielding wood-based materials in a bottom-up manner. When the sawdust-to-graphene ratio was 1:1, the conductivity and shielding of the material were 100 S/cm and 49 dB, respectively. Moreover, this composite material overcomes the anisotropy and inconsistent mechanical properties of natural wood.