Construction of nickel ferrite nanoparticle-loaded on carboxymethyl cellulose-derived porous carbon for efficient pseudocapacitive energy storage

The preparation of biomass-derived carbon electrode materials with abundant active sites is suitable for development of energy-storage systems with high energy and power densities. Herein, a hybrid material consisting of highly-dispersed nickel ferrite nanoparticle on 3D hierarchical carboxymethyl cellulose-derived porous carbon (NiFe2O4/CPC) was prepared by simple annealing treatment. The synergistic effects of NiFe2O4 species with multiple oxidation states and 3D porous carbon with a large specific surface area offered abundant active centers, fast electron/ion transport, and robust structural stability, thereby showing the excellent performance of the electrochemical capacitor. The best performing sample (NiFe2O4/CPC-800) exhibited a superior capacitance of 2894F g-1 at a current density of 0.5 A g-1. Encouragingly, an asymmetric supercapacitor with NiFe2O4/CPC-800 as a positive electrode and activated carbon as a negative electrode delivered a high energy density of 135.2 W h kg-1 along with an improved power density of 10.04 kW kg-1. Meanwhile, the superior cycling stability of 90.2% over 10,000 cycles at 5 A g-1 was achieved. Overall, the presented work offers a guideline for the design and preparation of advanced electrode materials for energy-storage systems.