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Silicon Metal-oxide-semiconductor Quantum Dots for Single-electron Pumping
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Pseudocapacitive Vanadium Nitride Quantum Dots Modified One-Dimensional Carbon Cages Enable Highly
Jun Yuan1,2, Min Qiu1,3, Xiang Hu1
1CAS Key Laboratory of Design and Assembly of Functional Nanostructures, and Fujian Provincial Key Laboratory of Materials and Techniques toward Hydrogen Energy, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, China.
ACS Nano
|August 18, 2022
Summary
We developed a novel sodium ion hybrid capacitor (SIHC) using vanadium nitride quantum dots in carbon nanofibers as an anode and activated carbon nanofiber cages as a cathode. This design overcomes kinetic incompatibility, enabling high energy density and long cycle life for advanced energy storage.
Area of Science:
- Materials Science
- Electrochemistry
- Nanotechnology
Background:
- Kinetic incompatibility between battery-type anodes and capacitive cathodes limits sodium-ion hybrid capacitor (SIHC) performance.
- Developing compatible electrode materials is crucial for advancing SIHC technology.
Purpose of the Study:
- To engineer a kinetics-compatible electrode design for SIHCs.
- To enhance sodium storage performance by addressing ion/electron transport limitations.
Main Methods:
- Fabrication of a freestanding anode using quantum-grade vanadium nitride (VN) nanodots anchored in N/F co-doped carbon nanofiber cages (VNQDs@PCNFs-N/F).
- Utilized activated N/F co-doped carbon nanofiber cages (APCNFs-N/F) as the cathode.
- Employed density functional theory (DFT) calculations to investigate Na+ adsorption and reaction kinetics.
Main Results:
- The coupled VN nanodots and carbon cages facilitated ion/electron transport and sodium storage reactions.
- DFT calculations confirmed enhanced Na+ adsorption/reaction activity and pseudocapacitance in the VNQDs@PCNFs-N/F anode.
- The assembled SIHC achieved high energy densities (157.1 Wh kg−1 at 198.8 W kg−1) and an ultralong cycling life (>8000 cycles).
Conclusions:
- The VNQDs@PCNFs-N/F anode effectively overcomes kinetic incompatibility in SIHCs.
- The study validates a kinetics-compatible electrode design strategy for metal-ion hybrid capacitors.
- This approach offers a promising pathway for developing high-performance energy storage devices.
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