A PEGylated deep eutectic solvent for "bubbling" synthesis of SnO2/SnS heterostructure for the stable lithium-ion storage.

Abstract

Constructing heterostructures is an effective strategy for the synthesis of high-performance anode electrode materials for lithium-ion batteries (LIBs). In this study, a "bubbling" PEGylated deep eutectic solvent (DES) method is utilized to synthesize SnO₂/SnS heterostructure nanodots anchored on carbon nanosheets (SnO₂/SnS@CN). A comprehensive investigation of the physical and chemical processes during the "bubbling" reaction offers in-depth insights into the underlying mechanism of the PEGylated DES approach. The carbon nanosheet structure enhances the electrical conductivity between SnO₂ particle units and, due to its excellent mechanical properties, significantly contributes to material stability. The nanodot configuration of the heterostructure further improves electron transfer and lithium-ion (Li⁺) migration within the SnO₂ units. The SnO₂/SnS@CN material exhibits outstanding Li⁺ storage performance, achieving a high capacity of 675.6 mA h/g at 1 A/g after 1000 cycles. These findings establish a theoretical foundation for preparing heterostructure anode materials using the "bubbling" PEGylated DES method.