Lignin-Derived Porous Carbons as Cathodes for Zinc-Ion Hybrid Capacitors

Abstract

Zinc-ion hybrid capacitors (ZIHCs) have emerged as attractive energy storage devices owing to their high energy density, fast charge–discharge capability, inherent safety, and low cost. However, their performance is often hindered by the imbalance in capacity and electrochemical kinetics between the porous carbon cathode (PCC) and the zinc (Zn) metal anode. Lignin, a renewable and widely available biomass resource, is rich in carbon and aromatic structures and possesses a complex three-dimensional (3D) molecular network, making it a promising precursor for the production of porous carbon materials with high yield, good electrical conductivity, and intrinsic heteroatom doping. Despite these advantages, the high-value utilization of lignin remains below 10%. This review systematically summarizes the main synthesis strategies for lignin-derived porous carbons (LDPCs) and recent progress in their application as cathode materials for ZIHCs. Emphasis is placed on pore structure engineering, surface chemistry modulation, and morphology control, and their roles in enhancing ion transport kinetics and charge storage behavior. Finally, key challenges and future research directions are discussed from mechanistic, technical, and practical perspectives, aiming to promote lignin valorization and advance the development of high-performance ZIHCs. © 2026 Wiley-VCH GmbH.