Surface-driven fast sodium storage enabled by Se-doped honeycomb-like macroporous carbon

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Carbon materials are crucial for sodium storage, but their performance needs enhancement.
• Selenium doping is a potential strategy to improve carbon structure and sodium storage, yet it remains underexplored.

Purpose of the Study:

• To synthesize and characterize a novel selenium-doped honeycomb-like macroporous carbon (Se-HMC) material.
• To investigate the sodium storage performance of Se-HMC as an anode material for sodium-ion batteries.

Main Methods:

• Surface crosslinking method using diphenyl diselenide and SiO2 nanospheres as template.
• Characterization of Se-HMC for its structure, surface area, and selenium content.
• Electrochemical testing of Se-HMC for sodium storage capacity, cycling stability, and rate performance.

Main Results:

• Se-HMC synthesized with >10% Se content and a high surface area (557 m² g⁻¹).
• Demonstrated surface-dominated Na storage via Se-assisted capacitive redox reactions.
• Achieved high reversible capacity (335 mA h g⁻¹ at 0.1 A g⁻¹), excellent stability (no loss after 800 cycles at 1 A g⁻¹), and ultrafast performance (251 mA h g⁻¹ at 5 A g⁻¹).

Conclusions:

• Se-HMC exhibits superior sodium storage performance due to its porous structure and selenium doping.
• The material demonstrates potential as a high-performance anode for fast-charging sodium-ion batteries.
• This work highlights selenium doping as an effective strategy for advanced carbon anode development.