Key Takeaways & Executive Findings
- •• Laser-produced graphene (LPG) from polyimide via CO2 laser irradiation yields multilayer graphene with sp2 C=C bonds and 3D sheet-like morphology. • LPG electrodes exhibit high areal capacitance of 51 mF cm−2 (170 F g−1) at 1 mA cm−2 in 1 M KOH, with energy density ~3.5 µWh cm−2 and power density ~350 µW cm−2. • Excellent cycling stability: 87% capacitance retention after 3,000 cycles in three-electrode configuration, and superior retention after 10,000 cycles in symmetric device. • Symmetric supercapacitor using LPG electrodes achieves specific capacitance of 23 mF cm−2, demonstrating practical potential for energy storage applications.
Abstract
We report an economical approach for the fabrication of laser-produced graphene (LPG) electrodes, which results in an improved electrochemical performance. Polyimide polymer was used as the starting material for LPG synthesis and was irradiated under ambient conditions with a CO2 laser. The prepared LPG samples were characterized by Raman spectroscopy and FTIR, which validated the formation of multilayer graphene containing sp2 hybridized C＝C bonds. FE-SEM revealed three-dimensional (3D) sheet-like structures, while HR-TEM images showed lattice planes with an interplanar spacing of approximately 0.33 nm, corresponding to the (002) plane of graphene. Their electrochemical performance showed a remarkable areal specific capacitance (CA) of 51 mF cm−2 (170 F g−1) at 1 mA cm−2 (3.3 A g−1) in a three-electrode configuration with 1 mol L−1 KOH as the aqueous electrolyte. The LPG electrodes produced an energy density of ～3.5 µWh cm−2 and a power density of ～350 µW cm−2, demonstrating significant energy storage ability. They also had an excellent cycling stability, retaining 87% of their specific capacitance after 3 000 cycles at 1 mA/cm2. A symmetric supercapacitor fabricated with LPG electrodes and the 1 mol L−1 KOH electrolyte had a specific capacitance of 23 mF cm−2 and showed excellent retention after 10 000 cycles, showing LPG’s potential for use in supercapacitors.
1. Introduction
In recent times, the energy sector has faced unprecedented challenges due to ever-growing energy consumption and concerns over environmental sustainability. Consequently, the development of effective energy storage technologies has become crucial. Electrochemical energy storage technology is of utmost importance in limiting the inherent inconsistencies of renewable energy sources and effectively meeting the escalating demands of contemporary society.
Among the several energy storage technologies, supercapacitors (SCs) have gained a lot of attention because of their quick charging and discharging kinetics, substantial power density, extended lifespan, low input impedance, and environmental toughness. Researchers are continually engaged in enhancing the specific capacitance and energy density of SCs despite their many benefits. Generally, charge storage mechanisms in SCs take place by forming an electrostatic double layer (EDL) at the interface between an electrode and an electrolyte and/or pseudocapacitive process. The electrode materials must exhibit favorable chemical kinetics, high chemical activity, reduced ion-diffusion path lengths, increased surface area, and numerous active sites for electrochemical reactions. For instance, Wang et al. synthesized 3D hierarchical ɑ-MnO2 nanotubes assembled hollow urchins, which provide electro-active sites and thereby find potential in improving the device performance. However, the electrochemical performance of SCs is affected by structural deterioration and inadequate contact between the electrode-current collector contact. Therefore, developing novel electrode components that can provide superior specific capacitance without any structural degradation is of utmost importance. The emergence of carbon-based nanomaterials, specifically graphene, has drawn much attention as electrode material in SCs due to extensive surface area (hypothetic...
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Gargi Dhiman, Kavita Kumari, Bon-Heun Koo, Faheem Ahmed, Nagih M. Shaalan, Saurabh Dalela, Parvez A. Alvi, Ranjeet Kumar Brajpuriya, Shalendra Kumar (2025). Electrochemical performance of a symmetric supercapacitor device designed using laser-produced multilayer graphene. SinoTechIntel Verified Research. https://doi.org/10.1016/S1872-5805(NCM2024-39-06-06)
Research & Educational Purpose Only:The translations, structured abstracts, analytical annotations, and data reports provided by SinoTechIntel are intended exclusively for academic research, internal corporate R&D, and educational benchmarking. They do not constitute formal engineering, chemical safety, legal, or professional advice.
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Frequently Asked Questions
What is laser-produced graphene (LPG) and how is it synthesized?
Laser-produced graphene (LPG) is a form of multilayer graphene synthesized by irradiating a polyimide polymer with a CO2 laser under ambient conditions. This economical method yields graphene with sp2 hybridized C=C bonds and a three-dimensional sheet-like structure, as confirmed by Raman spectroscopy, FTIR, FE-SEM, and HR-TEM.
What are the key electrochemical performance metrics of the LPG electrodes?
The LPG electrodes exhibit an areal specific capacitance of 51 mF cm−2 (170 F g−1) at 1 mA cm−2 in a three-electrode configuration with 1 M KOH electrolyte. They achieve an energy density of ~3.5 µWh cm−2 and a power density of ~350 µW cm−2, with 87% capacitance retention after 3,000 cycles.
How does the symmetric supercapacitor device perform?
A symmetric supercapacitor fabricated with LPG electrodes and 1 M KOH electrolyte shows a specific capacitance of 23 mF cm−2 and excellent retention after 10,000 cycles, demonstrating the practical potential of LPG for supercapacitor applications.
What are the advantages of using LPG as an electrode material?
LPG offers a cost-effective and scalable fabrication method, high surface area, good electrical conductivity, and excellent electrochemical stability. These properties contribute to its high specific capacitance, energy density, and cycling stability, making it a promising candidate for supercapacitor electrodes.
What characterization techniques were used to validate the formation of graphene?
The formation of multilayer graphene was validated using Raman spectroscopy and FTIR, which confirmed the presence of sp2 hybridized C=C bonds. FE-SEM revealed 3D sheet-like structures, and HR-TEM showed lattice planes with an interplanar spacing of approximately 0.33 nm, corresponding to the (002) plane of graphene.
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