Glucose-Modified MoS2 Cathode for Aqueous Zinc-Ion Batteries: Electrochemical performance with electrolytes of Zn (OTf) 2 vs. ZnSO4

Abstract

Zinc-ion batteries (ZIBs) have garnered significant research interest due to their inherent safety, cost-effectiveness, and the abundance of raw materials. Among the promising cathode materials, molybdenum disulfide (MoS2), with its distinctive layered structure, has demonstrated substantial potential for Zn2+ ion storage. This study introduces a simple and effective method to engineer the MoS2 layered structure. Through glucose-assisted chemical modification, the structural stability and interlayer ordering of MoS2 are enhanced while fully preserving its original crystalline phase. This modification leads to a notable improvement in electrochemical performance, particularly when paired with an optimized electrolyte. The study underscores the critical role of electrolyte selection in determining battery stability and lifespan. We investigated the performance of a ZIB using a glucose-modified MoS2 cathode in two aqueous electrolytes: 1 M ZnSO4 and 1 M Zn (CF3SO3)2. Comprehensive structural and electrochemical analyses, including XRD, SEM, IR, EDX, CV, EIS, and charge/discharge cycling, were performed. The results show that the Gl-m-MoS2 using the Zn(CF3SO3)2 electrolyte exhibits superior cycling stability and, by the 50th charge/discharge cycle, reaches a capacity of 114.68 mAh g-1 at a current density of 0.1 A g-1, corresponding to a 29.4% decrease.