Simultaneously formed and embedding-type ternary MoSe₂/MoO₂/nitrogen-doped carbon for fast and stable Na-ion storage

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Sodium-ion batteries (SIBs) are a promising alternative to lithium-ion batteries due to the abundance of sodium.
• Developing high-performance electrode materials is crucial for advancing SIB technology.

Purpose of the Study:

• To design and synthesize a novel ternary heterophase material for enhanced sodium-ion storage.
• To achieve high capacity, rate capability, and long-term cycling stability in SIB electrodes.

Main Methods:

• A supermolecule-assisted strategy was employed using MoO4^2-/polydopamine supermolecules and sulfonated polystyrene microspheres.
• In situ synthesis resulted in a hollow microspherical structure composed of ultrathin nanosheets.
• The structure features MoSe2 and MoO2 nanocrystallites embedded in a nitrogen-doped carbon matrix.

Main Results:

• The MoSe2/MoO2/carbon material demonstrated a high Na-ion storage capacity of 461 mA h g^-1 at a high current density of 70 A g^-1.
• The electrode exhibited outstanding cycle performance, retaining 610 mA h g^-1 after 1000 cycles.
• The layered MoSe2 provides high capacity, while MoO2 and carbon enhance rate performance and stability.

Conclusions:

• The rationally designed MoSe2/MoO2/carbon ternary heterophase material shows significant potential for high-performance sodium-ion batteries.
• The unique nanostructure and composition contribute to superior electrochemical performance, including excellent rate capability and cycling stability.