Constructing hollow flower-like molybdenum disulfide nanospheres/carbon nanospheres as anode with enhanced diffusion kinetics for lithium storage

Abstract

Molybdenum disulfide (MoS₂) has been considered a potential candidate anode electrode for next-generation high-performance lithium-ion batteries (LIBs) in terms of its high theoretical capacity. Nevertheless, the unsatisfactory electrochemical behavior, including unstable cycling performance and poor rate capability, caused by low electronic conductivity, frail layered structure, and huge volumetric during cycling, hinders its practical application. Synthesizing MoS₂-based composites with rationally designed structure and catalytic activity to boost the reaction kinetics of conversion reaction is important but still a challenge. In this work, hollow flower-like molybdenum disulfide nanospheres/carbon (MoS₂/C) nanospheres were prepared via a facile solvothermal synthesis and heat treatment process. As expected, benefiting from the uniquely prepared hollow flower-like structure and the introduction of conductive carbon, the intrinsic drawbacks are effectively alleviated, resulting in super electrochemical performance of a high reversible capacity of 425.8 mAh g⁻¹ at 20.0 A g⁻¹, and a high capacity of 538.2 mAh g⁻¹ with a high coulomb efficiency of over 99.9% after 1300 cycles at 1.0 A g⁻¹. Furthermore, the quantitative kinetic analysis results prove that pseudo-capacitance dominates total capacity behavior (76.7% at 0.5 mV⁻¹). Besides, the galvanostatic intermittent titration technique (GITT) was applied to identify the fast diffusion coefficient of the electrodes. This work offers an effective strategy for the subsequent preparation of transition metal sulfides for energy storage electrodes.