Nano ZnO-Doped Sweet Basil-Based Activated Carbon Electrodes for Supercapacitors

Year 2025, Volume: 9 Issue: 4, 1110 - 1120, 26.12.2025

M.firat Baran , Erdal Ertaş , Abdulkadir Levent

https://doi.org/10.31015/2025.4.13

Abstract

The production of highly efficient and cost-effective electrode materials is critical for the performance of energy storage systems, and therefore nanocomposite materials are ideal candidates for supercapacitor applications. In this study, the synthesis, characterization and electrochemical behavior of SBAC@ZnO nanocomposite obtained by modifying activated carbon (AC) synthesized by activating Sweet Basil (SB) plant with ZnO were investigated in detail. The structural and morphological properties of the SBAC nanocomposite were analyzed using UV-Vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD) techniques. The results indicate that the ZnO particles exhibit a homogeneous distribution on the SBAC surface and support the functionalization of organic functional groups derived from SB. Electrochemical performance evaluations were conducted using cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance spectroscopy (EIS) techniques. In CV analyses, the specific capacitance values of the SBAC and SBAC@ZnO electrodes in Na₂SO₄ electrolyte were obtained as 102.56 F/g and 229.96 F/g, respectively. In GCD experiments, the SBAC@ZnO electrode achieved a substantial Csp value of 426.66 F/g at a current density of 0.1 A/g. The EIS study revealed equivalent series resistance (ESR) values of 48.52 Ω for SBAC and 29.32 Ω for SBAC@ZnO, with charge transfer resistances (Rct) measured at 4.20 Ω and 3.28 Ω, respectively. The results demonstrate that ZnO doping diminishes internal resistance at the electrode-electrolyte interface, enhances ion transport, and optimizes electrochemical kinetics. Bode phase analyses indicated phase angles of 54.46° and 67.65° for SBAC and SBAC@ZnO electrodes, respectively, showing that ZnO doping enhances capacitive behavior. In the low-frequency region, the SBAC electrode reached a capacitance of 161.20 F/g, while the SBAC@ZnO reached a capacitance of 241.61 F/g. The findings indicate that ZnO doping significantly improves electrochemical performance, making the SBAC@ZnO nanocomposite a promising electrode material for supercapacitor applications.

Keywords

Plant-Based Nanomaterial , SBAC@ZnO nanocomposite , Supercapacitors , Galvanostatic charge-discharge , Cyclic voltammetry

References

• Anandhi, P., Harikrishnan, S., Mahalingam, S., Kumar, V. J. S., Lai, W. C., Rahaman, M., & Kim, J. (2024). Efficient and stable supercapacitors using rGO/ZnO nanocomposites via wet chemical reaction. Inorganic Chemistry Communications, 166, 112675. https://doi.org/10.1016/j.inoche.2024.112675
• Azizi, S., Askari, M. B., Rozati, S. M., & Masoumnezhad, M. (2024). Nickel ferrite coated on carbon felt for asymmetric supercapacitor. Chemical Physics Impact, 8, 100543. https://doi.org/10.1016/j.chphi.2024.100543
• Baran, A., Ertaş, E., Baran, M. F., Eftekhari, A., Gunes, Z., Keskin, C., Khalilov, R. (2024). Green-synthesized characterization, antioxidant and antibacterial applications of CtAC/MNPs-Ag nanocomposites. Pharmaceuticals, 17(6), 772. https://doi.org/10.3390/ph17060772
• Baran, A., Ertaş, E. (2025). Preparation, characterization and in vitro applications of morin hydrate loaded HPAC@MNPs nanocomposite. Journal of the Institute of Science and Technology, 15(1), 217-227. https://doi. org/10.21597/jist.1533345
• Chatterjee, D. P., & Nandi, A. K. (2021). A review on the recent advances in hybrid supercapacitors. Journal of Materials Chemistry A, 9(29), 15880-15918. https://doi.org/10.1039/D1TA02505H
• Costentin, C., & Savéant, J. M. (2019). Energy storage: pseudocapacitance in prospect. Chemical Science, 10(22), 5656-5666. https://doi.org/10.1039/C9SC01662G
• Ding, C., Fu, K., Pan, Y., Liu, J., Deng, H., & Shi, J. (2020). Comparison of Ag and Agi-modified ZnO as heterogeneous photocatalysts for simulated sunlight driven photodegradation of metronidazole. Catalysts, 10(9), 1097. https://doi.org/10.3390/catal10091097
• Divani, S., Paknejad, F., Ghafourian, H., Alavifazel, M., & Ardakani, M. R. (2017). Feasibility Study on Reducing Lead and Cadmium Absorption in Sweet Basil (Ocimum basilicum L.) With Using Active Carbon. Journal of Crop Nutrition Science, 3(1), 25-36. https://oiccpress.com/jcns/article/view/5847
• El-Khawaga, A. M., Elsayed, M. A., Gobara, M., Suliman, A. A., Hashem, A. H., Zaher, A. A., Salem, S. S. (2025). Green synthesized ZnO nanoparticles by Saccharomyces cerevisiae and their antibacterial activity and photocatalytic degradation. Biomass Conversion and Biorefinery, 15(2), 2673-2684. https://doi.org/10. 1007/s13399-023-04827-0
• Ertaş, E., Doğan, S., Baran, A., Baran, M. F., Evcil, M., Kurt, B., Aslan, K. S. (2025). Preparation and Characterization of Silver‐Loaded Magnetic Activated Carbon Produced from Crataegus Monogyna for Antimicrobial and Antioxidant Applications. ChemistrySelect, 10(16), e202405558. https://doi.org/10.1002/ slct.202405558
• Fayazi, M. (2024). Synthesis of ZnO nanostructures with different morphologies on biochar support for photocatalytic degradation of organic dye. Journal of Water and Environmental Nanotechnology, 9(2), 137-148. https://doi.org/10.22090/jwent.2024.02.02
• George, N. S., Singh, G., Bahadur, R., Kumar, P., Ramadass, K., Sathish, C. I., Vinu, A. (2024). Recent Advances in Functionalized Biomass‐Derived Porous Carbons and their Composites for Hybrid Ion Capacitors. Advanced Science, 11(35), 2406235. https://doi.org/10.1002/advs.202406235
• Güneş, M., Ertaş, E., Tumur, S., Zulfugarova, P., Nuriyeva, F., Kavetskyy, T., Kukhazh, Y., Grozdov, P., Šauša, O., Smutok, O., Ganbarov, D., & Kiv, A. (2025). Synthesis and Antibacterial Evaluation of Silver-Coated Magnetic Iron Oxide/Activated Carbon Nanoparticles Derived from Hibiscus esculentus. Magnetochemistry, 11(7), 53. https://doi.org/10.3390/magnetochemistry11070053
• Habib, W., Saji, A., Paul, F., Markapudi, P. R., Wilson, C., & Manjakkal, L. (2025). Flexible electrochemical capacitors based on ZnO-carbon black composite. Results in Engineering, 25, 104510. https://doi.org/10.1016/ j.rineng.2025.104510
• Huang, T., Jiang, Y., Shen, G., & Chen, D. (2020). Recent advances of two‐dimensional nanomaterials for electrochemical capacitors. ChemSusChem, 13(6), 1093-1113. https://doi.org/10.1002/cssc.201903260
• Inbaraj, B. S., Sridhar, K., & Chen, B. H. (2021). Removal of polycyclic aromatic hydrocarbons from water by magnetic activated carbon nanocomposite from green tea waste. Journal of Hazardous Materials, 415, 125701. https://doi.org/10.1016/j.jhazmat.2021.125701
• Kumar, R. D., Nagarani, S., Balachandran, S., Brundha, C., Kumar, S. H., Manigandan, R., Kim, S. H. (2022a). High performing hexagonal-shaped ZnO nanopowder for Pseudo-supercapacitors applications. Surfaces and Interfaces, 33, 102203. https://doi.org/10.1016/j.surfin.2022.102203
• Kumar, N., Kim, S. B., Lee, S. Y., & Park, S. J. (2022b). Recent advanced supercapacitor: a review of storage mechanisms, electrode materials, modification, and perspectives. Nanomaterials, 12(20), 3708. https://doi.org/10.3390/nano12203708
• Kumar, S., Ahmed, F., Shaalan, N. M., Arshi, N., Dalela, S., & Chae, K. H. (2023). Influence of Fe Doping on the Electrochemical Performance of a ZnO-Nanostructure-Based Electrode for Supercapacitors. Nanomaterials, 13(15), 2222. https://doi.org/10.3390/nano13152222
• Levent, A., & Saka, C. (2024). Enhanced electrochemical performance of ZnO@sulphur-doped carbon particles for use in supercapacitors. Journal of Energy Storage, 78, 110120. https://doi.org/10.1016/j.est.2023.110120
• Levent, A., & Saka, C. (2025a). Stable electrode material for use in supercapacitor with iodine doping after sulfonation of mesoporous activated carbon particles based on microalgae biomass. Biomass Conversion and Biorefinery, 1-14. https://doi.org/10.1007/s13399-025-06696-1
• Levent, A., & Saka, C. (2025b). Tunable energy storage in acidic and alkaline electrolytes using a NiO-embedded N, P-Doped biomass-derived electrode. Biomass and Bioenergy, 202, 108225. https://doi.org/10.1016/ j.biombioe.2025.108225
• Li, S., Tan, X., Li, H., Gao, Y., Wang, Q., Li, G., & Guo, M. (2022). Investigation on pore structure regulation of activated carbon derived from sargassum and its application in supercapacitor. Scientific Reports, 12(1), 10106. https://doi.org/10.1038/s41598-022-14214-w
• Li, Z., Zhou, Z., Yun, G., Shi, K., Lv, X., & Yang, B. (2013). High-performance solid-state supercapacitors based on graphene-ZnO hybrid nanocomposites. Nanoscale Research Letters, 8(1), 473. https://doi.org/10.1186/ 1556-276X-8-473
• Luo, L., Lan, Y., Zhang, Q., Deng, J., Luo, L., Zeng, Q., Zhao, W. (2022). A review on biomass-derived activated carbon as electrode materials for energy storage supercapacitors. Journal of Energy Storage, 55, 105839. https://doi.org/10.1016/j.est.2022.105839
• Mallick, S., Bag, S., & Retna Raj, C. (2025). Supercapacitors for energy storage: Fundamentals and materials design. Journal of Chemical Sciences, 137(3), 65. https://doi.org/10.1007/s12039-025-02394-7
• Mandal, S., Hu, J., & Shi, S. Q. (2023). A comprehensive review of hybrid supercapacitor from transition metal and industrial crop based activated carbon for energy storage applications. Materials Today Communications, 34, 105207. https://doi.org/10.1016/j.mtcomm.2022.105207
• Mehdi, R., Naqvi, S. R., Khoja, A. H., & Hussain, R. (2023). Biomass derived activated carbon by chemical surface modification as a source of clean energy for supercapacitor application. Fuel, 348, 128529. https:// doi.org/10.1016/j.fuel.2023.128529
• Olabi, A. G., Abbas, Q., Al Makky, A., & Abdelkareem, M. A. (2022). Supercapacitors as next generation energy storage devices: Properties and applications. Energy, 248, 123617. https://doi.org/10.1016/j.energy. 2022.123617
• Öziç, C., Ertaş, E., Baran, M. F., Baran, A., Ahmadian, E., Eftekhari, A., Yıldıztekin, M. (2024). Synthesis and characterization of activated carbon-supported magnetic nanocomposite (MNPs-OLAC) obtained from okra leaves as a nanocarrier for targeted delivery of morin hydrate. Frontiers in Pharmacology, 15, 1482130.
• Qiu, W., Xiao, H., Yu, M., Li, Y., & Lu, X. (2018). Surface modulation of NiCo2O4 nanowire arrays with significantly enhanced reactivity for ultrahigh-energy supercapacitors. Chemical Engineering Journal, 352, 996-1003. https://doi.org/10.1016/j.cej.2018.04.118
• Raha, S., & Ahmaruzzaman, M. (2022). ZnO nanostructured materials and their potential applications: progress, challenges and perspectives. Nanoscale Advances, 4(8), 1868-1925. https://doi.org/10.1039/D1NA00880C
• Ratha, S., & Samantara, A. K. (2018). Supercapacitor: instrumentation, measurement and performance evaluation techniques. Springer.
• Rudra, S., Seo, H. W., Sarker, S., & Kim, D. M. (2024). Supercapatteries as hybrid electrochemical energy storage devices: current status and future prospects. Molecules, 29(1), 243. https://doi.org/10.3390/ molecules29010243
• Saka, C., & Levent, A. (2024). Fabrication of nitrogen and ZnO doped on carbon particles obtained from waste biomass and their use as supercapacitor electrodes for energy storage. International Journal of Hydrogen Energy, 90, 1070-1083. https://doi.org/10.1016/j.ijhydene.2024.10.061
• Saka, C., & Levent, A. (2025). Robust and highly mesoporous magnesium oxide and nitrogen atoms incorporated hierarchical porous carbon particles as electrode material for high-performance energy storage in acidic, neutral, and basic electrolytes. Environmental Science and Pollution Research, 1-13. https://doi.org/10.1007/ s11356-025-36871-w
• Selvakumar, M., Bhat, D. K., Aggarwal, A. M., Iyer, S. P., & Sravani, G. (2010). Nano ZnO-activated carbon composite electrodes for supercapacitors. Physica B: Condensed Matter, 405(9), 2286-2289. https://doi.org/ 10.1016/j.physb.2010.02.028
• Solmaz, A., Turna, T., & Baran, A. (2024). Removal of paracetamol from aqueous solution with zinc oxide nanoparticles obtained by green synthesis from purple basil (Ocimum basilicum L.) waste. Biomass Conversion and Biorefinery, 14(9), 10771-10789. https://doi.org/10.1007/s13399-024-05355-1
• Sulciute, A., Nishimura, K., Gilshtein, E., Cesano, F., Viscardi, G., Nasibulin, A. G., Rackauskas, S. (2021). ZnO nanostructures application in electrochemistry: influence of morphology. The Journal of Physical Chemistry C, 125(2), 1472-1482. https://doi.org/10.1021/acs.jpcc.0c08459
• Wang, G., Zhang, L., & Zhang, J. (2012). A review of electrode materials for electrochemical supercapacitors. Chemical Society Reviews, 41(2), 797-828. https://doi.org/10.1039/C1CS15060J
• Wu, C., Zhang, F., Xiao, X., Chen, J., Sun, J., Gandla, D., Ein-Eli, Y., & Tan, D. Q. (2021). Enhanced Electrochemical Performance of Supercapacitors via Atomic Layer Deposition of ZnO on the Activated Carbon Electrode Material. Molecules, 26(14), 4188. https://doi.org/10.3390/molecules26144188
• Yadav, R., Sharma, S., Borkar, H., & Kumari, K. (2025). Zinc Oxide‐Enhanced Porous Activated Carbon From Waste Walnut Shells for Supercapacitor Electrodes. Energy Storage, 7(3), e70154. https://doi.org/10.1002/ est2.70154
• Yaseen, M., Khattak, M. A. K., Humayun, M., Usman, M., Shah, S. S., Bibi, S., Hasnain, B. S. U., Ahmad, S. M., Khan, A., Shah, N., Tahir, A. A., & Ullah, H. (2021). A Review of Supercapacitors: Materials Design, Modification, and Applications. Energies, 14(22), 7779. https://doi.org/10.3390/en14227779
• Yasin, A. S., hyun Kim, D., & Lee, K. (2021). One-pot synthesis of activated carbon decorated with ZnO nanoparticles for capacitive deionization application. Journal of Alloys and Compounds, 870, 159422. https:// doi.org/10.1016/j.jallcom.2021.159422
• Zhang, S., & Pan, N. (2015). Supercapacitors performance evaluation. Advanced Energy Materials, 5(6), 1401401. https://doi.org/10.1002/aenm.201401401