Bioinspired highly anisotropic, robust and environmental resistant wood aerogel composite with semi-interpenetrating polymer networks for Cu(II) ion removal

Aerogels, as attractive absorbents, have played essential roles in water treatment due to their light weight, high porosity, and exceptional absorption capacity. Nevertheless, conventional synthetic aerogel usually shows isotropic architectures, unsatisfactory mechanical performance, complex preparation process, and scale-limited fabrication, greatly limiting its applications in water remediation. In this study, inspired by the anisotropic architecture of natural wood, a biomimetic strategy was reported to prepare anisotropic, robust and environmental resistant aerogel composites via assembling semi-interpenetrating polymer networks (semi-IPNs) into the delignified wood template. The anisotropic structure endows the aerogel with excellent anisotropic mechanical behavior. The intermolecular hydrogen bonds of the cellulose microfibrils, the strong interfacial hydrogen bonds between cellulose chains and PI polymer networks, as well as the covalent bonds of semi-IPNs systems enable the aerogel composites to have a high yield strength of 566 kPa and Young's modulus of 56.335 MPa. The resulting aerogel composite exhibits a high saturation adsorption capacity of 296 mg g(-1) at about 100 min for Cu(II) ions. The composite is easily regenerated and recycled five cycles without apparent removal efficiency loss. This study presents a promising, eco-friendly, low-cost, and feasible strategy for scalable fabricating anisotropic, robust, highly efficient, and environmental resistant aerogel composites for heavy metal ions removal. [GRAPHICS] .

Automated summary

Inspired by the anisotropic architecture of natural wood, this study reports a biomimetic strategy to fabricate anisotropic, robust, and environmental resistant aerogel composites. The resulting composite exhibits excellent anisotropic mechanical behavior and high adsorption capacity for heavy metal ions.