Construction of Supercapacitor-Based Ionic Diodes with Adjustable Bias Directions by Using Poly(ionic liquid)
Jianze Feng1,2,3, Yan Wang1, Yongtai Xu1,3
1Laboratory of Clean Energy Chemistry and Materials, State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, 730000, P. R. China.
Advanced Materials (Deerfield Beach, Fla.)
|June 24, 2021
Summary
Researchers developed bias-direction-adjustable supercapacitor-diodes (CAPodes) using ionic liquids. These novel CAPodes enable charge storage in either the positive or negative bias direction, advancing capacitive ionic diode technology.
Area of Science:
- Materials Science
- Electrochemistry
- Energy Storage
Background:
- Supercapacitor-diodes (CAPodes) integrate diode functionality with electrical-double-layer capacitors.
- Existing CAPodes are limited to charge storage in the positive-bias direction.
- Applications include grid stabilization, signal propagation, and logic operations.
Purpose of the Study:
- To develop bias-direction-adjustable CAPodes.
- To overcome the unidirectional charge storage limitation of conventional CAPodes.
- To enhance the performance of capacitive ionic diodes.
Main Methods:
- Utilized an asymmetric carbon-based supercapacitor architecture.
- Employed polycation-based ionic liquid (IL) or polyanion-based IL as electrolytes.
- Investigated charge storage characteristics under different bias directions.
Main Results:
- Achieved CAPodes with charge-storage function exclusively in the positive- or negative-bias direction.
- Demonstrated a high rectification ratio (≈80% for rectification ratio II, RRII).
- Exhibited an outstanding cycling life of 4500 cycles.
Conclusions:
- Successfully realized bias-direction-adjustable CAPodes.
- Represent a significant advancement for designing high-performance capacitive ionic diodes.
- Pave the way for new applications of supercapacitors in electronics and energy systems.
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