Micronano channel fiber construction and its super nanofluidic ionic conductivity

Nanofluids are widely used in seawater desalination, energy conversion, and ion circuits, and the ordered channel structure can improve the ion transport properties of such nanofluids. Biomass-based nanofluids has revealed flaws, such as uncontrollable construction of nanostructure, the weak interaction of structural components, low ionic conductivity, unsatisfactory long-term reliability underwater, and insufficient energy conversion efficiency. Herein, in this study, micronano channel fiber was constructed by self-twisting microfluidic spinning cellulose nanocrystals (CNCs) to obtain aligned nanostructures with an orientation of 0.77. An ordered arrangement and stable bonding formed between the CNCs make their mechanical properties and electrical conductivity improve significantly. It exhibited excellent mechanical properties, with a tensile strength of 450 MPa. The cellulose fibers had a conductivity of 5.5 mS/cm in a 10 −5  M KCl solution. The steady-state ordered arrangement micronano channels and regularly arranged hydroxyl functional groups formed by self-twisting effect, which promotes ion transport with higher diffusion coefficient of K + than Cl − . This work can promote the application of pure cellulose in high-performance osmotic energy conversion systems.