Multiple heterointerfaces boosted de-/sodiation kinetics towards superior Na storage and Na-Ion full battery

Abstract

In this article, an effective strategy (viz., constructing multiple heterointerfaces) is proposed to develop superior electrode materials for sodium-ion battery (SIB), which is the most promising alternative to market-dominant lithium-ion battery for stationary energy storage. In the as-prepared heterogeneous-SnO₂/Se/graphene (h-SSG) composite, there exists multiple phase interfaces, including heterointerfaces between tetragonal and orthorhombic SnO₂ (t-/o-SnO₂) in the heterogeneous SnO₂ nanojunctions and two phase interfaces between t/o-SnO₂ and amorphous Se. These multiple phase interfaces promise the much improved Na storage properties of h-SSG when compared to four controls without such multiple heterointerfaces because the multiple built-in electric fields at the heterointerfaces can significantly boost the surface reaction kinetics and facilitate charge transport as demonstrated by kinetics analyses, theoretical calculations and contrastive electrochemical tests. Moreover, h-SSG also exhibits superior Na-ion full cell performance when coupled with a high-voltage Na₃V₂(PO₄)₂O₂F cathode. In view of the universality of the heterointerface-based enhancement effect on surface reaction and charge transport kinetics and the facile preparation procedures, the present strategy should be universal to develop other superior electrode materials for high-performance SIBs and other batteries for future energy storage applications.