Agglomeration-resistant 2D nanoflakes configured with super electronic networks for extraordinary fast and stable sodium-ion storage

Abstract

Abstract The promising 2D materials for sodium ion battery always suffer from dramatically sluggish electronic and ionic transport due to the irreversible agglomeration phenomenon. In order to tackle this problem, ethylene glycol is adopted in this work as a soft template in directing the growth of 2D structure based on the chelating ability and hydrogen-bonding chains. Subsequently, ethylene glycol could be in-situ transformed into carbon super electronic networks after the thermal treatment, to dramatically enhance the electrical conductivity and prevent the agglomeration of 2D sheets. Since the highly dispersed nanoflake structures and super electronic network could offer nano-sized effects and ultrashort ion-transport paths, the agglomeration-resistant Na3V2(PO4)3 (NVP) nanoflake displays exciting rate capabilities (about 71.2\u202fmAh\u202fg−1 at 200\u202fC, and 56.2\u202fmAh\u202fg−1 at the ultrahigh rate of 300\u202fC) and ultralong lifecycles. Our results suggest the potential application of 2D nano-structured NVP cathodes for transportation and large-scale grid storage.