Study on the Performance of Aniline Electrodeposited on MnO2 Nanowire as an Anode for Sodium-Ion Batteries

Abstract

Manganese dioxide is an ideal anode for sodium-ion batteries due to its rich crystal shapes. However, its low conductivity, low reversible discharge capacity, slow diffusion kinetics, and poor cyclic stability limit its potential for industrial application. The design of manganese dioxide (MnO2) with various morphologies, such as nanowires, nanorods, and nanoflowers, has proven effective in enhancing its electrochemical performance. Stacking nanowire structures is of interest as they increase the open space by forming an interconnected network, thus facilitating favorable diffusion pathways for sodium ions. Concurrently, the substantial increase in the electrolyte contact area efficiently mitigates the strain induced by the volume expansion associated with the repetitive migration and insertion of sodium ions. Based on previous research, this work presents the structural design of flexible MnO2/polyaniline (MnO2/PANI) nanowires assembled on carbon cloth (CC), an innovation in MnO2 modification. Compared to conventional MnO2 nanowires, the MnO2/PANI nanowires exhibit enhanced structural stability and improved dynamic performance, thereby marking a significant advancement in their material properties. This MnO2/PANI composite exhibits a rate capacity of approximately 200 mA h g−1 after 60 cycles at a current density of 0.1 A g−1, and maintains a rate capacity of 182 mA h g−1 even after 200 cycles under the same current density. This study not only provides new insights into the underlying mechanisms governing energy storage in MnO2/PANI nanowires but also paves the way for their further development and optimization as anodes for sodium-ion batteries, thereby opening up fresh avenues for research and application.