α‑Fe₂O₃@PANI Core–Shell Nanowire Arrays as Negative\nElectrodes for Asymmetric Supercapacitors

Abstract

Highly ordered three-dimensional\nα-Fe₂O₃@PANI core–shell nanowire\narrays with enhanced specific areal capacity and rate performance\nare fabricated by a simple and cost-effective electrodeposition method.\nThe α-Fe₂O₃@PANI core–shell nanowire\narrays provide a large reaction surface area, fast ion and electron\ntransfer, and good structure stability, which all are beneficial for\nimproving the electrochemical performance. Here, high-performance\nasymmetric supercapacitors (ASCs) are designed using α-Fe₂O₃@PANI core–shell nanowire arrays as anode\nand PANI nanorods grown on carbon cloth as cathode, and they display\na high volumetric capacitance of 2.02 mF/cm³ based on the\nvolume of device, a high energy density of 0.35 mWh/cm³ at a power density of 120.51 mW/cm³, and very good cycling\nstability with capacitance retention of 95.77% after 10 000\ncycles. These findings will promote the application of α-Fe₂O₃@PANI core–shell nanowire arrays as advanced\nnegative electrodes for ASCs.