Nanoscale insights in core–shell structure formation and property regulation of isotropic pyrolytic carbon materials

Abstract

Isotropic pyrolytic carbon (IPC) is renowned for its robust mechanical, biological, and tribological properties. However, the current mechanisms for modulating IPC microstructure are insufficient to achieve higher performance. Herein, this study provides nanoscale insights into the formation and property regulation of the core–shell structure of the IPC, integrating simulation and experimental approaches. Large-scale reactive molecular dynamics simulations elucidate the microstructural evolution and assembly processes from precursors to nanoparticles and intertwined graphene networks. Simulation process characterization enable versatile adjustment of IPC microstructural features and one-step deposition of hybrid structures with disordered cores and ordered shell layers. Compared to Pyrolytic carbon (PyC) with laminated graphene arrangement, the prepared hybrid structure enables rapid assembly of large-size standalone carbon components. Moreover, the hybrid architecture effectively improves the core–shell phase connection and significantly increases the interfacial shear stress within the intertwined graphene shell layers. Consequently, it greatly improves load transfer efficiency and enhances crack-bridging toughening effect. The endeavor to establish precise microstructure formation and property regulation in IPC materials promises to steer high-performance carbon materials toward distinct developmental trajectories.