Self-assembled dandelion-like NiS nanowires on biomass-based carbon aerogels as electrode material for hybrid supercapacitors

Abstract

Carbon aerogels derived from biomass have low specific capacity due to the underutilized structure, limiting their application in high-performance supercapacitors. In this work, the hierarchical nickel sulfide/carbon aerogels from liquefied wood (LWCA-NiS) were synthesized via a simple two-step hydrothermal method. Benefitting from the unique 3D coral-like network structure of LWCA, self-assembled NiS nanowires with the dandelion-like structure showed high specific surface (389.1 m²·g⁻¹) and hierarchical pore structure, which increased affluent exposure of numerous active sites and structural stability, causing superior energy storage performance. As expected, LWCA-NiS displayed high specific capacity (131.5 mAh·g⁻¹ at 1 A·g⁻¹), good rate performance, and highly reversible and excellent cycle stability (13.1% capacity fading after 5000 cycles) in the electrochemical test. Furthermore, a symmetrical supercapacitor using LWCA-NiS-10 as the electrode material delivered an energy density of 12.7 Wh·kg⁻¹ at 299.85 W·kg⁻¹. Therefore, the synthesized LWCA-NiS composite was an economical and sustainable candidate for the electrodes of high-performance supercapacitors.