Plasma‐Enabled Ternary SnO2@Sn/Nitrogen‐Doped Graphene Aerogel Anode for Sodium‐Ion Batteries

Abstract

AbstractSnO2‐based sodium‐ion batteries usually suffer from rapid capacity fading during the sodiation/desodiation caused by aggregation and cracking of Sn and irreversible formation of Na2O. In this respect, we design a ternary SnO2@Sn core‐shell structure decorated on a nitrogen‐doped graphene aerogel (SnO2@Sn/NGA), which is fabricated by using a microwave plasma‐based process. The converted Na2O can prevent agglomeration of Sn, thus stabilizing the structure during the cycles. Close contact between Na2O and Sn ensures Na+ ion diffusion to the Sn core and reversible conversion of Sn SnO2. Moreover, the deoxygenation effect of the plasma on NGA improves its degree of graphitization and electrical conductivity, which substantially improves the electrode rate performance. As a result, the SnO2@Sn/NGA anode delivers a high initial discharge capacity of 448.5 mAh g−1 at 100 mA g−1. Importantly, this unique nanohybrid electrode design can be extended to advanced anode materials for both lithium‐ and sodium‐ion batteries.