Continuous MXene fibers with near-gigapascal tensile strength via radial confinement and axial stretching.

Assembling titanium carbide MXene nanosheets into macroscopic high-performance fibers is very challenging because of the voids caused by transverse wrinkles, hindering their practical applications in wearable smart textiles. Here we continuously fabricate ultrastrong MXene fibers by coaxial-wet-spinning-assisted radial confining integrated with roll-to-roll-assisted axial stretching under near room temperature. Wet-spun MXene fibers are bridged with calcium ions and radially confined to reduce the voids resulting from transverse wrinkles by an in-situ bridged sodium alginate encapsulation layer, followed by stretching to axially align nanosheets. The resultant MXene fibers provide record tensile strength (958 MPa) and electrical conductivity (13,692 S cm-1). Large-area textiles made from the MXene fibers present extraordinary electromagnetic interference shielding capacity (6,509 dB cm-1). The proposed strategy opens an avenue for scalable assembling other two-dimensional nanosheets into high-performance fibers.