Non‐Equilibrium Carbothermal Shock Upcycling: Atomically Precise Synthesis of Tailored SiC Polytypes and Novel Hybrid Graphene from Complex Composites

Abstract The complex, heterogeneous nature of challenging precursors, as seen in end‐of‐life wind turbine blades, typically comprises glass or carbon fiber‐reinforced polymer composites with polyvinyl chloride foam cores. This complexity poses a significant material synthesis challenge, particularly for achieving high‐value recovery with precise structural control. A transformative one‐step, ultrafast carbothermal shock (CTS) process is presented that selectively converts these intricate, unseparated composites into high‐value SiC polytypes or novel graphene structures. Leveraging ultrafast Joule heating, CTS enables remarkable atomic‐scale phase control, facilitating kinetic trapping of specific non‐equilibrium structures such as metastable 6H‐SiC and a unique hybrid AB‐turbostratic graphene. This unique hybrid graphene combines the high charge carrier mobility of AB‐stacked nanodomains with the enhanced mechanical interlocking of turbostratic nanodomains. This results in exceptional electrical conductivity (1791 S m −1 ) and substantial mechanical reinforcement (+21.8%) in composites, significantly outperforming conventional reduced graphene oxide. Multiscale characterization and simulations elucidate the atomic‐scale mechanisms driving this phase evolution and kinetic trapping. The study establishes a new paradigm for advanced materials synthesis from complex feedstocks, transforming critical waste into on‐demand functional materials with compelling environmental benefits and dramatically lower operational costs. This sets the stage for sustainable material innovation and a circular economy.