EMI shielding of cobalt, red onion husk biochar and carbon short fiber‐PVA composite on X and Ku band frequencies

摘要

Abstract This present study discusses the effects of doped novel cobalt‐onion peel‐based water soluble Poly vinyl alcohol (PVA) composite for its electromagnetic interference shielding (EMI) effectiveness in high‐frequency bands such as X and Ku region. The primary aim of this study was to prepare a flexible electromagnetic shielding material for protecting electronic gadgets from the EMI effect. The biochar particles were prepared from red onion peel and mixed with cobalt/chopped carbon fiber (CCF) to form a compound structure. According to the results, the biochar and CCF addition improved the relative permittivity up to 9.6. Similarly, the hysteresis analysis showed a broad “S” curve for 2 vol cobalt‐added PVA composite. Moreover the doped composites are better in mechanical properties and the highest tensile strength of 79 MPa with Shore‐D hardness of 37 was noted for PV3 composite designation. Finally, the highest wave shielding of −44.37 dB and − 49.62 dB for X and Ku band were observed for composite designation PVA4. This EMI shielding effectiveness improved composites could be used as shielding material for modern industrial, defense, and medical applications.