Synthesis, analysis, and characterization of NiCo layered double hydroxide nanosheets on hollow biomass carbon for high-performance supercapacitors

NiCo layered double hydroxide (NiCo-LDH) nanosheets are considered as the most promising electrodes for supercapacitors due to its excellent electrochemical properties. However, the slower electron transport rate and poor cycling stability hinder its development. In this paper, tubular biomass carbon (BC) materials are obtained through carbonization and activation with typha orientalis as a carbon precursor. Subsequently, NiCo-LDH nanosheets are vertically cultivated on the BC surface through a solvothermal process. The unique orthogonal structure of composite reduces the agglomeration of NiCo-LDH and enhances the electrochemical active sites. In addition, the tubular structure of BC can alleviate the volume expansion during charging and discharging process and while providing fast routes for electrons/ions to enhance the charge transfer rate. Benefiting from these advantages, the fabricated NiCo-LDH/BC composite results in a high specific capacity (1044 C g⁻¹ at 1 A g⁻¹). The assembled hybrid supercapacitor based on NiCo-LDH/BC and active carbon delivers a superior energy density of 86.71 W h kg⁻¹ at 873.32 W kg⁻¹ and cycling stability (92.33% after 10,000 cycles). This research presents certain reference value and significance for actual applications of superior LDH-based materials in electrochemical energy storage applications.