A pyrolyzed polyacrylonitrile/selenium disulfide composite cathode with remarkable lithium and sodium storage...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Pyrolyzed polyacrylonitrile/sulfur (pPAN/S) is a cathode material for lithium-sulfur batteries that mitigates polysulfide dissolution.
• Limitations of pPAN/S include low sulfur content (<50 wt%) and insufficient capacity utilization, hindering energy density for commercial use.

Purpose of the Study:

• To develop a novel cathode material with enhanced active material content and superior electrochemical performance for lithium and sodium storage.
• To investigate the potential of pyrolyzed polyacrylonitrile/selenium disulfide (pPAN/SeS2) composites as high-performance cathode materials.

Main Methods:

• Synthesis of pyrolyzed polyacrylonitrile/selenium disulfide (pPAN/SeS2) composite.
• Electrochemical testing of pPAN/SeS2 in lithium-ion and sodium-ion battery configurations.

Main Results:

• The pPAN/SeS2 composite achieved a high active material content of 63 wt%.
• For lithium storage, pPAN/SeS2 delivered a capacity of >1100 mAh g⁻¹ at 0.2 A g⁻¹ with stable cycling over 2000 cycles at 4.0 A g⁻¹.
• In room temperature sodium-ion batteries, pPAN/SeS2 achieved a capacity of >900 mAh g⁻¹ at 0.1 A g⁻¹ and maintained stable cycling for over 400 cycles at 1.0 A g⁻¹.

Conclusions:

• pPAN/SeS2 composites exhibit significantly enhanced active material content and superior electrochemical performance compared to traditional pPAN/S materials.
• The developed pPAN/SeS2 material demonstrates great potential for high-energy-density lithium and sodium storage applications.