Rationally Incorporated MoS₂/SnS₂ Nanoparticles on Graphene Sheets for Lithium-Ion and Sodium-Ion Batteries

Abstract

Herein, we have designed and first synthesized a unique ternary hybrid structure by simultaneously growing SnS₂ and MoS₂ particles on graphene sheets (denoted as MoS₂/SnS₂-GS) via one-pot hydrothermal route. The charge incompatibility between MoO₄^2- and graphene oxide with negative charged functional groups on surface can be compromised with the aid of Sn⁴⁺ cations, which renders the final formation of SnS₂ and MoS₂ on GS surface. This is the first report of the cohybridization of MoS₂ and SnS₂ with GS matrix from anionic and cationic precursors in the absence of premedication of graphene surface. When MoS₂/SnS₂-GS acts as anodes for lithium-ion batteries, the hybrids exhibit much better cycling stability than MoS₂-GS and SnS₂-GS counterparts. The compact adhesion of MoS₂/SnS₂ nanoparticles helps offset the undesired result of destruction of electrode materials resulting from volume expansion during repeated cycles. Furthermore, by combination with their synergetic effect on interface and the presence of discrepant asynchronous electrochemical reactions for SnS₂ and MoS₂, MoS₂/SnS₂-GS hybrids are endowed with improvement of electrochemical capabilities. Besides, they also showed outstanding Na-storage ability.