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Evaluating the Electrochemical Properties of Supercapacitors using the Three-Electrode System
Published on: January 7, 2022
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A high-performance supercapacitor of vertically-oriented few-layered graphene with high-density defects
Jun Lei Qi1, Xu Wang, Jing Huang Lin
1State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology, Harbin 150001, China. fengjc@hit.edu.cn wdfei@hit.edu.cn.
Nanoscale
|February 3, 2015
Summary
Researchers developed vertically-oriented few-layered graphene (VFG) with improved water wettability for supercapacitors. This 3D graphene, enhanced by surface defects, shows high capacity and stability, making it ideal for advanced energy storage devices.
Area of Science:
- Materials Science
- Electrochemistry
- Nanotechnology
Background:
- 3D graphene structures are crucial for supercapacitors but suffer from poor water wettability, hindering practical applications.
- Vertically-oriented few-layered graphene (VFG) offers a promising 3D architecture for energy storage.
Purpose of the Study:
- To develop a method for creating 3D VFG with enhanced wettability for supercapacitor applications.
- To investigate the relationship between surface defects, wettability, and electrochemical performance in VFG.
Main Methods:
- Plasma-enhanced chemical vapor deposition (PECVD) for VFG synthesis.
- Scanning and transmission electron microscopy (STEM) for structural analysis.
- Raman spectroscopy for material characterization.
- Contact angle (CA) measurements to assess wettability.
- Electrochemical analyses to evaluate supercapacitor performance.
Main Results:
- VFG samples exhibited a significant reduction in contact angle from 131° to 73° with increasing surface defect density, indicating improved wettability.
- VFG with high defect density achieved specific capacities up to 704 μF cm⁻².
- Demonstrated good cycling stability with approximately 91.2% capacitance retention after 3000 cycles.
Conclusions:
- Surface defects in VFG stimulate increased wettability, leading to enhanced supercapacitor performance.
- The developed VFG is a promising candidate for ultrathin, high-performance supercapacitor electrodes.
- This work addresses the wettability challenge in 3D graphene for practical energy storage solutions.
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