Template-Guided Assembly of Silk Fibroin on Cellulose Nanofibers for Robust Nanostructures with Ultrafast Water Transport

Abstract

The construction of multilength scaled hierarchical nanostructures from diverse natural components is critical in the progress toward all-natural nanocomposites with structural robustness and versatile added functionalities. Here, we report a spontaneous formation of peculiar "shish kebab" nanostructures with the periodic arrangement of silk fibroin domains along straight segments of cellulose nanofibers. We suggest that the formation of these shish kebab nanostructures is facilitated by the preferential organization of heterogeneous (β-sheets and amorphous silk) domains along the cellulose nanofiber driven by modulated axial distribution of crystalline planes, hydrogen bonding, and hydrophobic interactions as suggested by all-atom molecular dynamic simulations. Such shish kebab nanostructures enable the ultrathin membrane to possess open, transparent, mechanically robust interlocked networks with high mechanical performance with up to 30 GPa in stiffness and 260 MPa in strength. These nanoporous robust membranes allow for the extremely high water flux, up to 3.5 × 10 L h m bar combined with high rejection rate for various organic molecules, capability of capturing heavy metal ions and their further reduction into metal nanoparticles for added SERS detection capability and catalytic functionalities.

Ultrathin and Flexible CNTs/MXene/Cellulose Nanofibrils Composite Paper for Electromagnetic Interference Shielding

“…Cellulose nanofibrils (CNFs), which can be isolated by (2,2,6,6-tetramethylpiperidin-1-yl) oxidanyl (TEMPO) oxidation and mechanical processing from wood and plants, are composed of numerous aligned β-D-(1 → 4)glucopyranose polysaccharide chains with abundant strongly intermolecular hydrogen bonds [42][43][44][45]. With excellent mechanical toughness, integrating high stiffness about 140 GPa and a lightweight character [46][47][48], CNFs have been considered as a promising emerging class of high-performance naturederived nanomaterials [49][50][51][52]. Moreover, CNFs with a typical 1D nanofiber structure will generate less insulating contacts between conductive nanosheets, such as reduced graphene oxide nanosheets [53], boron nitride nanosheets [54], and MXene nanosheets [55].…”

Design of ultrathin hybrid membranes with improved retention efficiency of molecular dyes

“…As a matter of fact, dyes are discharged into water and into the environment by various industries working, for example, in the paper, cosmetics, leather, and textiles sectors to name just a few, because dyes are part of the chemicals used to impart special properties to their products. 1,2 Dyes are usually classied into anionic, cationic and non-ionic (neutral) molecules, are stable to light and resistant to biological degradation and aerobic digestion. Although chemical, physical, and biological methods are frequently used to remove dyes form industrial effluents, adsorption is considered the cheapest and most effective method compared to the all the available dye removal strategies.…”

Biopolymer nanofibrils: Structure, modeling, preparation, and applications

“…The pore size and porosities in the CNF membranes can be optimized through crosslinking [413], hot-pressing [414], and reducing membrane thickness [415]. CNFs can further integrate with other components, such as GO [416] and silk fibroin [417] to generate water purification membranes. The spontaneous formation of peculiar "shish-kebab" nanostructures with the periodic arrangement of silk fibroin domains along straight segments of CNFs was reported ( Figure 27C and D) [417].…”

“…CNFs can further integrate with other components, such as GO [416] and silk fibroin [417] to generate water purification membranes. The spontaneous formation of peculiar "shish-kebab" nanostructures with the periodic arrangement of silk fibroin domains along straight segments of CNFs was reported ( Figure 27C and D) [417]. The formation of these "shish-kebab" nanostructures was facilitated by the preferential organization of heterogeneous (β-sheets and amorphous silk) domains along the CNFs, driven by the modulated axial distribution of crystalline planes, hydrogen bonding, and hydrophobic interactions.…”

“…The formation of these "shish-kebab" nanostructures was facilitated by the preferential organization of heterogeneous (β-sheets and amorphous silk) domains along the CNFs, driven by the modulated axial distribution of crystalline planes, hydrogen bonding, and hydrophobic interactions. The nanoporous membranes allowed for high water flux, up to 3.5 ×10 4 L h −1 m −2 bar −1 , combined with a high rejection rate for various organic molecules and metal ions ( Figure 27E) [417].…”