A Multidimensional Topotactic Host Composite Anode Toward Transparent Flexible Potassium-Ion Microcapacitors.

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Transparent flexible supercapacitors (TFSCs) are crucial for future electronics but suffer from low energy density and compromised transparency.
• Existing TFSCs often rely on aqueous electrolytes and pseudocapacitive mechanisms, limiting performance.

Purpose of the Study:

• To develop a high-energy-density transparent flexible supercapacitor (TFSC) that overcomes current limitations.
• To explore a novel potassium-ion microcapacitor with enhanced performance characteristics.

Main Methods:

• Designed and fabricated a transparent flexible potassium-ion microcapacitor.
• Utilized a multidimensional topotactic host composite anode for energy storage.
• Investigated a battery-supercapacitor hybrid storage mechanism and an enlarged working voltage.

Main Results:

• Achieved a high energy density of 15.5 μWh cm⁻².
• Demonstrated a significantly enlarged working voltage of 3 V.
• The novel anode facilitated synchronous potassium-ion and electron uptake, creating an efficient 3D transport system.

Conclusions:

• The developed potassium-ion microcapacitor outperforms state-of-the-art TFSCs.
• The study provides design principles for high-performance TFSCs at both material and device levels.
• This work paves the way for practical transparent flexible electronics powered by advanced energy storage.