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Evaluating the Electrochemical Properties of Supercapacitors using the Three-Electrode System
Published on: January 7, 2022
Energy-controlled supercapacitors based on polybenzidine-oxidant-GO hybrid electrodes with vanadate and dichromate
Aisan Moshgabadi1, Reza Dadashi1, Khalil Farhadi2,3
1Department of Analytical Chemistry, Faculty of Chemistry, Urmia University, Urmia, Iran.
Scientific Reports
|June 14, 2026
Summary
Researchers synthesized polybenzidine (PB) on anodized graphite substrates using vanadate and dichromate oxidants for supercapacitor applications. Vanadate-assisted synthesis yielded superior electrochemical performance and energy density in hybrid supercapacitors.
Area of Science:
- Materials Science
- Electrochemistry
- Polymer Chemistry
Background:
- Supercapacitors are crucial energy storage devices.
- Developing high-performance electrode materials is key for advancing supercapacitor technology.
- Polymer-metal oxide hybrids offer synergistic properties for enhanced electrochemical performance.
Purpose of the Study:
- To synthesize polybenzidine (PB) in situ on anodized graphite substrates (AGS) using dichromate and vanadate oxidants.
- To systematically evaluate the electrochemical performance of the synthesized PB-AGS materials for supercapacitor applications.
- To investigate the influence of different oxidants on the polymerization pathway, metal-polymer interaction, and resulting hybrid architecture.
Main Methods:
- In situ synthesis of polybenzidine on anodized graphite substrates using dichromate and vanadate oxidants.
- Structural characterization using ATR-IR, Raman, FE-SEM, EDX, and XRD.
- Electrochemical performance evaluation in a three-electrode system and a symmetric device configuration using a gel-polymer electrolyte.
Main Results:
- Successful synthesis and characterization of polybenzidine-metal oxide hybrid materials on AGS.
- PB-V/AGS electrodes exhibited higher specific capacitance (1080 mF cm⁻²) compared to PB-C/AGS (920 mF cm⁻²).
- The symmetric PB-V/AGS supercapacitor achieved a higher capacitance (50 F g⁻¹), energy density (12.63 mWh g⁻¹), and comparable power density (168.5 mW g⁻¹) to PB-C/AGS, with good cycling stability (88% retention after 5000 cycles).
Conclusions:
- Vanadate and dichromate-assisted in situ synthesis provides a viable route for fabricating high-performance polymer-metal oxide hybrid supercapacitors.
- The choice of oxidant significantly influences the structure-property relationships and electrochemical performance.
- The developed PB-V/AGS material demonstrates significant potential for advanced energy storage applications.
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