In Situ Growth of a Feather‐like MnO2 Nanostructure on Carbon Paper for High‐Performance Rechargeable Sodium‐Ion Batteries

Abstract Recently, sodium‐ion batteries have attracted great attention, owing to the rich resource and low cost. In the present work, a feather‐like MnO 2 nanostructure was prepared directly on carbon paper by using a rapid and simple hydrothermal route for the first time. The formation mechanism was proposed by investigating the intermediate products during the reaction. When applied as an anode for a sodium‐ion battery, the feather‐like MnO 2 nanostructure on carbon paper exhibited a high discharge capacity, good rate reversibility, and long‐term cycling stability. A high specific capacity of approximately 300 mAh g −1 could be obtained even after cycling 400 times with a current density of 0.1 A g −1 . Furthermore, the Na + storage mechanism of MnO 2 on carbon paper in the sodium‐ion battery was also investigated in this work. Such high performance can be attributed to the porous structure of the substrate and high specific surface area of the feather‐like nanostructure.