One-Step Calcination Process for the Construction of Oxygen Deficient Fe2O3/N, P Co-doped Carbon Composites for High-Performance Supercapacitors

To explore the high performance of supercapacitors, oxygen deficient Fe2O3/N, P co-doped carbon (N-Fe2O3/NPC) composites were successfully fabricated by the one-step calcination of a precursor of FeOOH/polyaniline composites via a simple strategy of introducing oxygen vacancy (denoted as oxygen defects). The influences of carbonization temperature and carbonization time on the electrochemical properties of the N-Fe2O3/NPC composites were investigated. The results show that N-Fe2O3/NPC-450-2h exhibits high capacitance (605 mF cm(-2) at a current density of 5 mA cm(-2)) and cycle life (100% after 2000 cycles). The assembled N-Fe2O3/NPC-450-2h-based symmetrical supercapacitor possesses a capacity retention rate of 100% after 5500 cycles at a current density of 10 mA cm(-2). In addition, the symmetrical supercapacitor shows a maximum energy density of 0.0148 mWh cm(-2) (0.255 mWh cm(-3)) when the power density is 0.8 mW cm(-2) (13.8 mW cm(-3)). N-Fe2O3/NPC-450-2h has broad application prospects as an electrode material for long-life symmetrical supercapacitors.