Biomimetic, antibiofouling graphdiyne-Ti3C2Tx MXene fiber fabrics for high-performance osmotic energy conversion

Abstract

Construction of advanced permselective membranes with strong surface charges, crosslinked hierarchical channels, and antibiofouling properties are needed to achieve high power density for harvesting sustainable osmotic energy in the marine environment. Herein, a biomimetic graphdiyne (GDY)-Ti₃C₂T_x MXene fiber fabrics (G-MFFs) with excellent ion permeability and selectivity based on a microfluidic wet-fused spinning and in situ polymerization strategy is reported. The decorated GDY improves antierosion quality and ion diffusion/rectification. The as-prepared G-MFFs with abundant ion migration channels and strong cation permselectivity exhibit increased Na⁺ ion diffusion capability (0.38 vs. 0.80 eV of MFFs) and a high transference number of Na⁺ ion. Therefore, the biomimetic permselective fabrics achieve a peak power density of 9.29 W m⁻² in natural seawater/river water and 74.55 W m⁻² under a 500-fold salinity gradient, far exceeding commercial standards. G-MFFs exhibit a promising long-term stability, high output power density with tunable fiber diameters and effective performance even under different pH levels (7.21–8.52 W m⁻² at pH 4–10). Moreover, G-MFFs exhibit exceptional resistance against biofouling (an antimicrobial rate of 99.96 %). Hence, this study may inspire the fabrication and expand the viability of functional fabric-based permselective devices for practical marine environment applications.