Rigid-Flexible Coupling Carbon Skeleton and Potassium-Carbonate-Dominated Solid Electrolyte Interface Achieving...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Potassium-ion energy storage is promising for large-scale applications.
• Large potassium ions cause electrode instability and poor durability in batteries.
• Developing stable electrode materials is crucial for advancing potassium-ion technology.

Purpose of the Study:

• To design a stable anode material for potassium-ion batteries.
• To improve the structural stability and ion dynamics of electrodes.
• To enhance the overall performance and cycling life of potassium-ion devices.

Main Methods:

• Fabrication of a bubble-wrap-like carbon sheet (BPCS) with a rigid-flexible porous architecture.
• Formation of a stable solid electrolyte interphase (SEI) dominated by K2CO3·1.5H2O nanograins.
• Electrochemical testing of BPCS in potassium-ion batteries and hybrid capacitors.

Main Results:

• BPCS exhibits excellent structural stability and accommodates volume expansion.
• The K2CO3·1.5H2O SEI enhances stability and provides efficient K+ diffusion pathways.
• Potassium-ion batteries with BPCS anodes show high reversible capacities (463 mAh g-1 at 50 mA g-1).
• The BPCS//NPC hybrid capacitor achieves high energy density (167 Wh kg-1) and long cycling life (80.8% retention over 10,000 cycles).

Conclusions:

• The bubble-wrap-like carbon sheet is a promising anode material for high-performance potassium-ion energy storage.
• The engineered SEI layer significantly contributes to the improved stability and ion transport.
• The developed materials and devices show potential to rival lithium-ion hybrid supercapacitors for energy storage applications.