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

Abstract

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