Electrospun Lignin-Based Carbon Nanofibers as Supercapacitor Electrodes

Lignin shows great potential for carbon-based functional materials and composite material electronics. However, high heterogeneity, poor thermal stability, and low molecular weight limit the practical application of lignin for fiber-shaped lignin-based materials, especially in the field of supercapacitors with high energy storage devices. Herein, a simple modification and fractionation strategy is designed to obtain lignin for the preparation of high-performance lignin-based carbon fibers (CFs). The modification and fractionation process effectively increases the molecular weight and reduces the heterogeneity of lignin. The introduction of lignin with large molecular weight and low heterogeneity is conducive to reduce the carbon weight loss of the precursor fibers, maintain the morphology of lignin-based CFs, and then significantly improve the specific surface area and energy storage properties. The specific surface area and energy storage density of the obtained lignin-based CFs reach 2042.86 m2/g and 442.2 F/g, respectively. This strategy provides a simple and effective method for the preparation of high-performance, low-cost, and green energy storage materials.