Nitrogen-Doped Porous Carbon Films from Polyacrylonitrile: A Transformative Approach for High-Stability Zinc Anodes

Area of Science:

• Electrochemistry
• Materials Science
• Energy Storage

Background:

• Zinc-ion batteries (ZIBs) offer a sustainable alternative to lithium-ion batteries but face anode stability issues.
• Zinc metal anodes suffer from dendrite formation, side reactions, and poor mechanical integrity, limiting ZIB practical application.

Purpose of the Study:

• To develop a stable and efficient anode for ZIBs by addressing the challenges of zinc metal anodes.
• To investigate the efficacy of a novel polyacrylonitrile (PAN)-derived N-heteroatom-doped porous carbon (c-PAN) coating for zinc anodes.

Main Methods:

• A scalable spray-coating technique was employed to apply a c-PAN coating onto zinc anodes.
• The coated anodes underwent preoxidation and laser-assisted carbonization to create a robust N-doped porous carbon structure.
• Electrochemical performance was evaluated using symmetrical and full-cell configurations with V2O5 cathodes.

Main Results:

• The c-PAN coating effectively stabilized the zinc anode interface, significantly reducing dendrite formation and enhancing Zn2+ ion transport.
• Symmetrical Zn//Zn cells with c-PAN/Zn anodes demonstrated exceptional cycling stability exceeding 2800 hours at 1.0 mA cm-2.
• Full cells (c-PAN/Zn∥V2O5) achieved a high specific capacity of 317 mAh g-1 at 0.2 A g-1 and retained 71% capacity after 1000 cycles at 1.0 A g-1.

Conclusions:

• The N-doped porous carbon network of the c-PAN coating provides superior mechanical strength, conductivity, and chemical stability compared to other carbonized polymer coatings.
• This PAN polymer-derived carbon coating technology shows significant promise for revolutionizing zinc-ion battery performance and enabling their widespread adoption.
• The developed c-PAN/Zn anode represents a significant advancement in addressing critical limitations for practical ZIB applications.