High S-doped amorphous carbon/carbon quantum dots coupled micro-frame for highly efficient potassium storage

Area of Science:

• Materials Science
• Electrochemistry
• Sustainable Energy

Background:

• Developing cost-effective anode materials for potassium-ion batteries (KIBs) with high performance remains a significant challenge.
• Waste recycling offers a sustainable approach to creating advanced battery materials.

Purpose of the Study:

• To synthesize a novel anode material from biomass waste for enhanced KIB performance.
• To investigate the structural and electrochemical properties of sulfur-doped amorphous carbon/carbon quantum dots coupled micro-frame (SCMF).

Main Methods:

• Chemical exfoliation and S/Se-assisted carbonization were employed to prepare SCMF from biomass waste.
• Electrochemical performance was evaluated in KIBs, including capacity, rate capability, and cycle life.
• Molecular dynamic simulations were used to understand potassium storage mechanisms.

Main Results:

• SCMF exhibited a high reversible capacity of 414.0 mAh g^-1 after 100 cycles at 100 mA g^-1.
• Excellent rate capability (224.0 mAh g^-1 at 2000 mA g^-1) and capacity retention (208.9 mAh g^-1 after 2000 cycles at 1000 mA g^-1) were achieved.
• Molecular simulations confirmed fast electron transport via carbon quantum dots and favorable interactions with potassium ions.

Conclusions:

• SCMF demonstrates significant potential as a high-performance anode material for KIBs, derived from recycled biomass.
• The integrated structure of amorphous carbon and carbon quantum dots effectively enhances potassium storage.
• This research highlights the viability of utilizing waste materials for sustainable secondary battery applications.