Evaluation of Gelation Time Affecting the Self-Assembled Framework of Lignin Nanoparticle-Based Carbon Aerogels and Their Electrochemical Performances

Renewable biomass-derived carbon aerogels have emerged as an attractive option in the promising field of the energy storage industry. Herein, lignin-resorcinol-formaldehyde cryogel (LRF) is successfully self-assembled into a 3D interlinked framework with beadlike chains by using lignin nanoparticles and green deep eutectic solvent as the cosolvent, and the resulting LRF-derived carbon aerogel (LRFC) with a typical microporous structure is subsequently prepared. We highlight the effects of the gelation time on the microstructures and properties of LRFC products. With a storage capacity of 284 F g –1 at 0.5 A g –1 and a remarkable cycle stability of 97% at 10 A g –1 over 5000 cycles, the as-prepared LRFC12 forming near the gel point exhibits exceptional electrochemical performance. Furthermore, the symmetric supercapacitor (SSC) constructed using two LRFC12 electrodes displays an impressive specific capacitance of 193 F g –1 at 0.5 A g –1 and a maximum energy density of 28.2 W h kg –1 at a power density of 262.6 W kg –1 .