Constructing Hierarchical Tectorum-like α-Fe2O3/PPy Nanoarrays on Carbon Cloth for Solid-State Asymmetric Supercapacitors.

The design of complex heterostructured electrode materials that deliver superior electrochemical performances to their individual counterparts has stimulated intensive research on configuring supercapacitors with high energy and power densities. Herein we fabricate hierarchical tectorum-like α-Fe₂O₃/polypyrrole (PPy) nanoarrays (T-Fe₂O₃/PPy NAs). The 3D, and interconnected T-Fe₂O₃/PPy NAs are successfully grown on conductive carbon cloth through an easy self-sacrificing template and in situ vapor-phase polymerization route under mild conditions. The electrode made of the T-Fe₂O₃/PPy NAs exhibits a high areal capacitance of 382.4 mF cm⁻² at a current density of 0.5 mA cm⁻² and excellent reversibility. The solid-state asymmetric supercapacitor consisting of T-Fe₂O₃/PPy NAs and MnO₂ electrodes achieves a high energy density of 0.22 mWh cm⁻³ at a power density of 165.6 mW cm⁻³. [ABSTRACT FROM AUTHOR]