Recent advances in structural design of conductive polymer composites for electromagnetic interference shielding

The proliferation of electronic devices and wireless communication in our daily lives has led to a significant increase in electromagnetic pollution. This issue poses a serious threat to the proper functioning of electronic equipment as well as human health. Therefore, the investigation of materials with superior electromagnetic interference (EMI) shielding capabilities has garnered growing interest. In this paper, the mechanisms of EMI shielding were first introduced briefly. It was noted that the development of advanced EMI shielding materials involved adhering to principles such as minimizing reflection loss, enhancing absorption loss, and incorporating multiple internal reflections. The construction and shielding properties of traditional EMI shielding materials were introduced. Unlike metal materials with high densities and reflection loss, lightweight conductive polymer composites (CPCs) have been the most promising EMI shielding materials. Meanwhile, carbon-based nanofillers such as carbon nanotubes and graphene nanosheets, along with two-dimensional transition metal carbonitrides MXenes Ti3C2Tx, have emerged as the most promising and versatile conductive nanofillers for CPCs. The EMI shielding performance and loss mechanism of CPCs with homogeneous structure, segregated structure, laminated structure, and porous structure were introduced in detail. It was noted that the EMI shielding performance could be significantly improved by incorporating multiple structures into the same CPCs, such as a rational combination of segregated and porous structures. Finally, the challenges and development trends of CPCs for EMI shielding applications were discussed.HighlightsMechanisms of EMI shielding were introduced from aspect of energy dissipation.Structure-property of traditional EMI shielding materials was described.EMI shielding performance of CPCs with different structures was summarized.Future challenges and growing trends of CPCs for EMI shielding were discussed.Absorption-dominated loss and multiple structure design were emphasized. The structural design of CPCs for EMI shielding mainly includes homogenous structure, porous structure, laminated structure, and segregated structure.image