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

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 MoO42- 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.