This study pioneers a transformative approach of discarded orange peels (Citrus sinensis) into highly porous carbon, demonstrating its potential application in energy storage devices. The porous carbon structure offers a substantial surface area, making it conducive for effective ion adsorption and storage, thereby enhancing capacitance. The comprehensive characterization, including X-ray diffraction, Fourier transform infrared, Raman spectroscopy, field emission scanning electron microscopy, and XPS verifies the material’s suitability for energy storage applications by confirming its nature, functional groups, graphitic structure, porous morphology and surface elemental compositions. Moreover, the introduced plasma treatment not only improves the material’s intensity, bending vibrations, and morphology but also increases capacitance, as evidenced by galvanostatic charge–discharge tests. The air plasma-treated carbon exhibits a noteworthy capacitance of 1916F/g at 0.05A/g in 2 M KOH electrolyte. long term cyclic stability has been conducted up to 10,000 cycles, the calculated capacitance retention and columbic efficiency is 92.7% and 97.6%. These advancements underscore the potential of utilizing activated carbon from agricultural waste in capacitors and supercapatteries, offering a sustainable solution for energy storage with enhanced performance characteristics.

High capacitance sustainable low-cost cold plasma exposed activated carbon electrode derived from orange peel waste to eco-friendly technique
    Abstract
    1 Introduction  
    2 Materials and methods
        2.1 Synthesis of orange peel activated carbon (OPAC)
        2.2 Electrode preparation
        2.3 Characteristics
    3 Results and discussion
        3.1 Yield analysis
        3.2 XRD analysis
        3.3 XPS analysis
        3.4 Raman spectroscopy analysis
        3.5 FTIR evaluation
        3.6 FE-SEM-field emission scanning electron microscope analysis
        3.7 Contact angle measurement
        3.8 Electrochemical impedance analysis
        3.9 Cyclic voltammetry analysis
        3.10 Galvanostatic charge–discharge analysis
    4 Conclusion
    References

• K. C. Sowmiya(Research Department of Physics, Sri Vasavi College Erode, Erode, Tamil Nadu, India) Corresponding author
• K. A. Vijayalakshmi(Research Department of Physics, Sri Vasavi College Erode, Erode, Tamil Nadu, India) Corresponding author