Hierarchical Co–C@PDA@BN/PAM composites: synergistic enhancement of microwave absorption and thermal conductivity through heterostructure design

Abstract

The development of modern electronic devices necessitates the creation of materials that exhibit both excellent thermal conductivity and high electromagnetic wave absorption performance. This study focuses on the synthesis of a dual-functional composite material, Co–C@PDA@BN, by incorporating boron nitride (BN) onto a metal–organic framework (MOF)-derived Co–C core through the strong adhesion properties of polydopamine (PDA). The heterogeneous structural interface enhances interfacial polarization, thereby optimizing wave absorption. The thermal conductivity can be improved by adjusting the ratio of Co–C to BN. A composite with a Co–C to BN ratio of 1 : 5 shows a minimum reflection loss of −55.3 dB at 5 wt% and a thermal conductivity of 0.396 W m⁻¹ K⁻¹, while a ratio of 1 : 20 achieves a thermal conductivity value of 0.464 W m⁻¹ K⁻¹ with a minimum reflection loss of −44.9 dB, demonstrating the facile tunability of these two properties. This work provides a promising pathway via heterostructure design to balance thermal conductivity and wave absorption characteristics, which may offer guidance for advancing electronic device technology.