A graphene/C-PDA/carbon fiber ternary heterostructure network enables lightweight polyimide composites with enhanced electromagnetic shielding and thermal management capabilities

Abstract

High-performance polymer composites (HFPCs) integrating electromagnetic interference (EMI) shielding and thermal conductivity (TC) are urgently needed for advanced electronics; however, challenges remain in achieving a balanced integration of TC, thermal stability, conductivity, and EMI shielding within a single material. Herein, we guided by interfacial engineering strategies present a polyimide (PI) composite featuring a ternary carbon heterostructure network, achieving an exceptional EMI shielding effectiveness of 95 dB and significantly enhanced TC (3.38 W m⁻¹ K⁻¹, a 1151% improvement over pure PI). The graphene/carbonized polydopamine/carbon fiber (CPPG) ternary carbon heterostructure network was realized via an interfacial engineering strategy (approach combining polydopamine-modulated interface modification and controlled in situ co-carbonization). The enhanced performance stems from the synergistic CPPG network, which facilitates electromagnetic wave (EMW) dissipation through multi-scale polarization loss while establishing continuous phonon transport pathways for efficient heat transfer. The graphene-wrapped fiber ternary heterostructure creates multi-scale heterostructure reflection interfaces, enhancing EMW conduction and polarization losses, while the continuous carbon skeleton ensures unimpeded phonon transport. The resulting PI composites exhibit a lightweight, thermally stable, and highly efficient dual-functional structure, making them promising candidates for next-generation aerospace electronics, integrated circuits, and high-frequency communication devices.