Enhanced Na-ion storage via creating smooth ions transportation pathways in a modified heterostructure

Abstract

Sodium-ion batteries (SIBs) have drawn evolutionary attention due to the urgent requirements for renewable energy storage. Unfortunately, the cycle stability and rate capability of promising SnO₂ materials are far from satisfactory. Herein, enhanced Na-ion storage via creating smooth ion transportation pathways in a modified heterostructure has been originally demonstrated. The tuned composite of uniformly dispersed SnO₂ particles anchored on the surface of graphene nanosheets was prepared via a facile hydrothermal treatment with the help of iodine. Inspiringly, an anticipated Na-ion storage can be successfully achieved, with reversible Na-ion storage of 486.1 mA h g⁻¹ at 50 mA g⁻¹ and rate capability of 343.8 mA h g⁻¹ even at 800 mA g⁻¹. The exceptional electrochemical property profited from the synergistic effect of the heterostructure with plentiful ion transportation pathways for fast Na-ion diffusion. This work opens a practical opportunity for the design of next-generation rechargeable batteries in energy storage.