Electrochemical synthesis of MnO2 porous nanowires for flexible all-solid-state supercapacitor

Abstract

MnO₂ porous nanowires were prepared with an Au-coated polycarbonate membrane as the template via a simple electrodeposition method. The obtained film could be used directly as a flexible all-solid-state supercapacitor electrode. The structures of the final product were characterized by various characterization techniques including scanning electron microscopy (SEM), X-ray diffraction (XRD), FT-IR spectra, and X-ray photoelectron spectroscopic (XPS). The electrochemical results showed that MnO₂ porous nanowire-based electrode materials had high capacitive performances. The areal capacitance of the prepared supercapacitor with a MnO₂ deposition time of 200 s was 44.6 mF cm⁻². Under different bending conditions, the areal capacitance of the supercapacitor still remained at 90.5%, indicating the highly flexible property. Furthermore, it nearly remained at 89.6% of its initial capacitive value after 2000 cycles at a current density of 0.4 mA cm⁻¹, showing its excellent cycle stability. However, the prepared supercapacitor can power a light-emitting-diode (LED) to meet practical applications for micro-power supplies.