ABSTRACT Sustainable electromagnetic interference shielding materials that combine environmental friendliness, robustness, and enhanced performance are critically needed for national development strategies. Wood-based materials, particularly woodchips, are desirable due to their chemical similarity to wood and the potential to eliminate anisotropic properties. In this study, chemically treated woodchips to expose the cellulose within them. The interactions between woodchips, graphene, and calcium ions (Ca²+) was studied to create innovative electromagnetic shielding wood-based materials using a bottom-up approach. Compared to composites formed via hydrogen bonding cross-linking, the introduction of calcium ions significantly increased the degree of cross-linking and improved the mechanical properties of the composites. This resulted in a tensile strength of 9.8 MPa, compressive strength of 43.8 MPa, and flexural strength of 22.3 MPa. By incorporating graphene, an optimal conductive network was established. At a sawdust-to-graphene ratio of 1:1, the material's conductivity and shielding effectiveness were 100 S/cm and 49 dB, respectively, meeting the standards for commercial and residential EMI shielding applications. Moreover, this composite material addresses the anisotropy and inconsistent mechanical properties of natural wood, showing significant potential in the area of green electronics.
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