Polyphosphazene-derived carbon modified nanowires for high-performance electrochemical energy storage

Two one-dimensional nanowires, Fe₃O₄and MnO₂nanowires, were modified with polyphosphazene-derived carbon (PZSC) usingin situpolymerization and high-temperature calcination methods. PZSC coated with MnO₂nanowire (MnO₂/PZSCNW) was designed as the positive electrode, while PZSC coated with Fe₃O₄nanowire (Fe₃O₄/PZSCNW) was designed as the negative electrode. Both MnO₂/PZSCNW (+) and Fe₃O₄/PZSCNW (-) exhibit much larger specific capacities than the corresponding MnO₂and Fe₃O₄nanowires, reaching 75.5 mAh g^-1and 75.9 mAh g^-1, respectively. The maximum specific capacity, power and energy density of MnO₂/PZSCNW (+)//Fe₃O₄/PZSCNW (-) in alkaline electrolyte are up to 63.2 mAh g^-1, 429.6 W kg^-1and 53.7 Wh kg^-1, respectively. After 10 000 cycles, the cell maintains 100% capacity. The experimental results indicate that the polyphosphazene-derived carbon coating can significantly improve the electrochemical performance, providing a feasible solution for constructing high-performance supercapacitors.