Fig. 3

1D nacre-inspired fibers reinforced by polymer crosslinking. a Polarized optical microscopy image of an as-spun gel-state GO fiber. b Corrugated surface, c near-circular cross-section, and d enlarged SEM image from c clearly showing the layered structure. e Optical images showing the formation of gel-state GO filaments as they exit the multi-hole spinneret for GO yarn synthesis. f Optical images of GO yarns produced as they are being pulled out from the bath for collection. g Tensile stress–strain curves of as-spun GO fibers prepared using various coagulation baths to induce crosslinking. Reproduced with permissions³⁹. h–j Schematic illustration of the LCST strategy and the resulting composite fibers, which shows the formation of host LCs of 2D nanoplatelets with uniform nanochannels (h), incorporation of guest compounds (i), and wet-spinning assembly of complex LCs into nacre-mimetic fibers with hierarchical structures (j). Morphology of the final nacre-inspired fibers from cross-section (k) and surface (l) showing a well-layered structure. m, n Photographs of thirty meter-long GO-HPG fibers (m) and a mat of GGO-HPG fibers made by hand (n). o Tensile stress–strain curves for neat GO (1), GO-HPG (2), and GO-HPG-GA (3) nacre-inspired fibers. Scale bar: 3 μm (k), 5 μm (l), and 1 cm (m, n). Reproduced with permission⁴⁰