Three-Dimensional Porous Carbon-Supported Co/Fe Bimetallic Nanoparticles Derived from Carboxymethyl Cellulose for Enhanced Supercapacitor Electrodes

The exploration of new high-performance, low-cost, and eco-friendly electrode materials is crucial for improving electrochemical performance. In this research, a three-dimensional interconnected porous composite electrode is synthesized, comprising bimetallic oxide of CoFe2O4 and Co3Fe7 alloy with porous carbon derived from carboxymethyl cellulose (CoFe2O4-Co3Fe7@C), through a straightforward high-temperature annealing process. Various characterizations are conducted on the CoFe2O4-Co3Fe7@C composites. The incorporation of CoFe2O4 and Co3Fe7 nanoparticles into the CMC-derived porous carbon enhances electron conduction pathways and reduces internal electrode resistance, resulting in outstanding electrochemical performance. When the CoFe2O4-Co3Fe7@C composite is carbonized at 700 °C with a current density of 0.5Ag-1, its specific capacitance reaches 3405.25Fg-1. At a power density of 321.44Wkg-1, an asymmetric supercapacitor with activated carbon as the positive and negative electrode and CoFe2O4-Co3Fe7@C-700 as the positive electrode has a maximum energy density of 187.59Whkg-1. Moreover, after 10,000 cycles, the composite shows 90.05% cycling stability. This study paves the way for innovation in energy storage technology.