Improving the Reaction Kinetics by Annealing MoS 2 /PVP Nanoflowers for Sodium-Ion Storage.

Under the ever-growing demand for electrochemical energy storage devices, developing anode materials with low cost and high performance is crucial. This study established a multiscale design of MoS 2 /carbon composites with a hollow nanoflower structure (MoS 2 /C NFs) for use in sodium-ion batteries as anode materials. The NF structure consists of several MoS 2 nanosheets embedded with carbon layers, considerably increasing the interlayer distance. Compared with pristine MoS 2 crystals, the carbon matrix and hollow-hierarchical structure of MoS 2 /C exhibit higher electronic conductivity and optimized thermodynamic/kinetic potential for the migration of sodium ions. Hence, the synthesized MoS 2 /C NFs exhibited an excellent capacity of 1300 mA h g -1 after 50 cycles at a current density of 0.1 A g -1 and 630 mA h g -1 at 2 A g -1 and high-capacity retention at large charge/discharge current density (80% after 600 cycles 2 A g -1 ). The suggested approach can be adopted to optimize layered materials by embedding layered carbon matrixes. Such optimized materials can be used as electrodes in sodium-ion batteries, among other electrochemical applications.