Rationally Incorporated MoS/SnS 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 SnS and MoS particles on graphene sheets (denoted as MoS/SnS-GS) via one-pot hydrothermal route. The charge incompatibility between MoO and graphene oxide with negative charged functional groups on surface can be compromised with the aid of Sn cations, which renders the final formation of SnS and MoS on GS surface. This is the first report of the cohybridization of MoS and SnS with GS matrix from anionic and cationic precursors in the absence of premedication of graphene surface. When MoS/SnS-GS acts as anodes for lithium-ion batteries, the hybrids exhibit much better cycling stability than MoS-GS and SnS-GS counterparts. The compact adhesion of MoS/SnS 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 SnS and MoS, MoS/SnS-GS hybrids are endowed with improvement of electrochemical capabilities. Besides, they also showed outstanding Na-storage ability.