Enhanced K-Storage Kinetics for N-Doped Carbon via Controllable Dedoping Strategy

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Carbonaceous materials are explored as low-cost anodes for potassium-ion batteries (PIBs).
• Existing carbon anodes suffer from volume expansion and poor stability during ion insertion/extraction.
• Nitrogen (N) doping can enhance potassium ion (K+) storage by creating active sites and increasing interlayer spacing.

Purpose of the Study:

• To investigate the impact of N-doping and subsequent dedoping on the potassium ion storage performance of carbon materials.
• To develop a simple, one-step synthesis strategy for nitrogen-doped carbon anodes.

Main Methods:

• A one-step pyrolysis method was used to synthesize various nitrogen-doped carbon materials.
• Electrochemical performance was evaluated, including cycling stability and rate capability.
• The synergistic effects of N-doping and carbon vacancy defects were analyzed.

Main Results:

• The synthesized nitrogen-doped carbon (PNC) exhibited excellent electrochemical performance.
• PNC demonstrated good long-term cycling stability, retaining 195 mAh/g after 300 cycles at 200 mA/g.
• The material showed outstanding rate performance, attributed to alleviated volume expansion and promoted K+ transport.

Conclusions:

• N-doping and the formation of carbon vacancies through dedoping effectively mitigate volume expansion in carbon anodes.
• The developed nitrogen-doped carbon materials offer a viable pathway for advanced anode design in potassium-ion batteries.
• This work provides insights for creating high-performance materials for efficient potassium ion storage.