Abstract
Cocos nucifera (Coconut hair oil) was burned using wick-and-oil technique (gas-phase combustion) known as flame synthesis method to obtain carbon soot for electrode material. Synthesized carbon soot was chemically activated using optimized ratio of activating agents ZnCl2 (1:1, wt. /wt.) and KOH (1:2, wt./wt.), followed by thermal treatment at 900 °C. XRD analysis showed that the coconut oil-derived carbon soot (CoCS) has a crystallite size of ~ 1.92 nm with an interlayer spacing of 3.62 Å. After chemical activation, the crystallite size slightly altered only, while a small increase in interlayer spacing was observed (3.65 Å for ZnCl₂ activation and 3.71 Å for KOH activation), revealing subtle structural modification of the carbon framework. SEM analysis revealed a well-connected microporous network with reduced agglomerate size after activation, while EDAX confirmed increased carbon content following chemical treatment. BET results showed a substantially enhanced surface area and mesoporous structure of the KOH-activated CoCS, leading to favorable pathways for electrolyte ion transport. Among the studied samples, KOH-activated CoCS demonstrated the best electrochemical performance, delivering a specific capacitance of ~ 176 F g⁻¹, with an energy density of ~ 6.11 Wh kg⁻¹ and a maximum power density of ~ 395 W kg⁻¹. The simple synthesis route, favorable structural characteristics, and competitive electrochemical performance highlight the potential of coconut oil-derived carbon soot as a scalable and sustainable electrode material for EDLC and other energy storage applications.
Data availability
The datasets used and/or analysed during the current study available from the corresponding author on reasonable request.
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Acknowledgements
The authors acknowledge access to the experimental facilities (BET and XPS) at the Material Research Centre (MRC), MNIT Jaipur India, is gratefully acknowledged. KM acknowledges financial support from Symbiosis International (Deemed University), Pune under MJRP grant (SIU/SCRI/MJRP/2024/4896) and Dassault Systèmes Foundation (DSF Contract ID: 2024–6854; DSF Project ID: IN-2024-1-08).
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A.T. wrote the main manuscript text. A.T., R.K. and R.G. procured data and interpret the results. C.R.K. Kant contributed to data analysis and experimental validation. K.M. assisted in data analysis, interpretation of results and manuscript editing. All authors reviewed the manuscript.
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Tyagi, A., Kumari, R., Gupta, R. et al. Electrochemical studies on Cocos nucifera (coconut hair oil) derived carbon soot as an electrode material for EDLC application using non-aqueous NaPF6 electrolyte. Sci Rep (2026). https://doi.org/10.1038/s41598-026-42749-9
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DOI: https://doi.org/10.1038/s41598-026-42749-9