Synergistic Enhancement of Regenerated Silk Fibroin Fibers via Ca2+ Crosslinking and MXene Nanosheet Reinforcement

Regenerated silk fibroin (RSF) fibers have garnered significant attention due to their remarkable biocompatibility and tunable biodegradability. However, their relatively poor mechanical performance limits their broader applications. Herein, we propose a simple and scalable one-step wet spinning approach to fabricate high-performance RSF composite fibers by incorporating two-dimensional Ti 3 C 2 T x MXene nanosheets and Ca 2+ ions. The synergistic reinforcement of Ca 2+ -induced and MXene-assisted β-sheet formation significantly enhanced the structural integrity and mechanical properties of the RSF fibers. The resulting composite fibers exhibited a high tensile strength (~234.1 MPa), improved thermal stability (MAXDTG ~ −2.1%/min), and increased glass transition temperatures (~179.0°C). In addition, both the microscopic morphology and the mechanical properties showed that the mechanical properties of the composite fiber are further enhanced after 2× stretching.