An Eco-Efficient and Sustainable Strategy for Fabricating High-Strength Agricultural Fibers.

High-value utilization of renewable biomass resources is of great significance for achieving ecological and societal sustainability. It remains highly desirable to convert agricultural residues into high-performance regenerated cellulose fibers in a green and scalable manner. However, the fabrication of superior agricultural regenerated fibers is demanding due to the inherent anti-depolymerization structure and low degree of polymerization of agricultural cellulose. Here, we demonstrated a recyclable and eco-efficient process enabling the selective extraction of cellulose from agricultural residues using a novel acid deep eutectic solvent system, and proposed a stretch-induced alignment and spatial confinement strategy to realize scalable fabrication of high-strength and high-toughness regenerated fibers. The deep eutectic solvent presented efficient delignification and tailoring capacity for agricultural residue, yielding cellulose with a high purity of 91.2% and a crystallinity of 72.6%. The resultant fibers addressed the intrinsic limitations of agricultural cellulose through the formation of aligned nanofibril structures and densified hydrogen-bonding networks, exhibiting a tensile strength of 852 MPa and a toughness of 110 MJ m