Biomimetic Biomass-Bsed Carbon Fibers: Effect of Covalent-BndConnection on Performance of Derived Carbon Fibers

The morphological collapse of pure biomass-based carbon fibers is the main challenge restricting its development. Inspiration comes from nature that cellulose and lignin in natural trees are linked by covalent-bonds, leading to good extensibility and stability of wood. In this work, an effective strategy is presented to connect lignin and cellulose-acetate by covalent-bond to obtain a novel carbon fiber precursor material. Isophorone diisocyanate was used as a chemical modifier to successfully connect lignin and cellulose-acetate through a covalent-bond, which is formed by the urethane reaction of isocyanate group and hydroxyl group. With the introduction of covalent-bond connection, the precursor fibers exhibit a large molecular weight, uniform molecular weight distribution, excellent thermal stability, and good spinnability. After thermo-stabilization and carbonization, the pure biomass-based carbon fibers are successfully prepared. The results of SEM, BET, tensile test, and electrochemical properties t...