Hierarchical Metal‐Carbon Interphases for Energy‐Coupled Multifunctional Fibre Composites

ABSTRACT Managing energy dissipation and multifunctional coupling in structural materials remains a central challenge for advanced aerospace and intelligent systems. Here, we present a design strategy that transforms a traditional aramid/polytetrafluoroethylene (AF/PTFE) composite into a multifunctional platform integrating thermal management, electrical conductivity, and mechanical reinforcement. Through in situ growth and reduction of a silver–organic framework on tannic‐acid‐activated fibers, a continuous silver–amorphous‐carbon (Ag‐C) network is constructed, forming hierarchical interphases that couple phonon‐electron transport with interfacial stress dissipation. The resulting composite exhibits an ≈82% increase in through‐thickness thermal conductivity, a ≈28% enhancement in interlaminar shear strength, and an electrical conductivity of 1.86 S cm− 1 , while maintaining stable performance under high thermal‐mechanical loads. The Ag‐C hybrid framework acts as a heat‐transfer highway and mechanical–electrical bridge, demonstrating how multiscale interfacial design can synchronize mechanical robustness with thermal–electrical regulation. This work advances beyond lubrication‐centered composites by establishing a universal strategy for constructing multifunctional, energy‐coupled materials. The concept provides a scalable route toward next‐generation functional composites capable of adaptive performance in extreme environments.