Improved performance of supercapacitor and zinc-ion battery based on 3D architectured porous manganese oxide-based nanosheets as binder-free electrodes

We demonstrate a rechargeable supercapacitor and aqueous zinc-ion battery (AZIB) with improved capacity and cyclability using MnO2 and silver nanoparticles-carbon nanotubes (AgCNT)-based electrode. The binder-free electrode, with three-dimensional (3D) architectured porous nanoparticle-derived MnO2 nanosheets (MnO2-NPS), is directly fabricated on AgCNT-modified substrates through a simple, cost-effective, and green electrodeposition process, where AgCNTs are uniformly covered on selected substrates through an immersion & dry process for further MnO2 deposition. With such a 3D porous wall-like network for providing adequate electroactive sites and facilitating electron/ion transfer during electrochemical processes and a AgCNT modification on substrate's surface for improving electrode's electrical conductivity and strengthening the interface adhesion between substrate and deposited MnO2, the MnO2-NPS-based electrodes exhibit appreciable cycling stability with high storage performances for both applications in AZIBs and supercapacitors. This research opens up opportunities to explore a promising 3D porous manganese oxide-based electrode for high-energy green low-cost energy storage devices.

Automated summary

This research presents a rechargeable supercapacitor and aqueous zinc-ion battery with improved capacity and cyclability. The MnO2-based electrode with a three-dimensional porous structure shows excellent cycling stability and high storage performance, providing potential for green and low-cost energy storage devices.