Evaluation of Millet Extract as Green Inhibitor for AA6063  Corrosion in 1 M KCl: From Electrochemical Studies to Optimisation

Ojo S.I. Fayomi; Onyeka G. Ogbuozobe; Ho Soon Min

doi:10.14233/ajchem.2026.35380

Issue

Vol. 38 No. 6 (2026): Vol. 38 Issue No 6, 2026

Issue Published : 31 May 2026

This work is licensed under a Creative Commons Attribution 4.0 International License.

Evaluation of Millet Extract as Green Inhibitor for AA6063 Corrosion in 1 M KCl: From Electrochemical Studies to Optimisation

https://doi.org/10.14233/ajchem.2026.35380

Ojo S.I. Fayomi

Department of Mechanical Engineering, Bells University of Technology, P.M.B. 1015, Ota, Ogun State, Nigeria; Department of Mechanical Engineering Science, University of Johannesburg, Auckland Park, Kingsway Campus, P.O. Box 534, Johannesburg, South Africa

https://orcid.org/0000-0001-9023-2371

Onyeka G. Ogbuozobe

Department of Mechanical Engineering, Bells University of Technology, P.M.B. 1015, Ota, Ogun State, Nigeria

https://orcid.org/0009-0002-4361-4793

Ho Soon Min

Faculty of Health and Life Sciences, INTI International University, Putra Nilai, 71800, Negeri Sembilan, Malaysia

https://orcid.org/0000-0002-3697-5091

Corresponding Author(s) : Onyeka G. Ogbuozobe

godsononyeka507@gmail.com

Asian Journal of Chemistry, Vol. 38 No. 6 (2026): Vol. 38 Issue No 6, 2026
Article Published : 31 May 2026

Abstract

This study presents a comprehensive evaluation of millet extract as a green corrosion inhibitor for the protection of AA6063 in a 1 M KCl solution medium. The research integrates multiple electrochemical techniques, including open circuit potential (OCP) measurements and linear sweep voltammetry (LSV), alongside detailed adsorption studies. These are further complemented by the application of response surface methodology (RSM) to enhance and optimize the inhibitor’s performance. A central composite design (CCD) was strategically employed to systematically vary key experimental parameters, specifically, the concentration of millet extract and the operating solution temperature. The electrochemical investigations provided deeper insights into the underlying inhibition mechanism, while the RSM framework enabled the identification of optimal operating conditions for corrosion control. The resulting second-order polynomial model was rigorously validated through analysis of variance (ANOVA), which confirmed the statistical significance and strong influence of both concentration and temperature on the corrosion rate. The optimal conditions were determined at a concentration of 0.284 g and a temperature of 33.56 ºC, resulting in a low corrosion rate of 0.332 mm yr^–1. This study concludes that millet extract is an effective and environmentally friendly corrosion inhibitor, offering a viable, sustainable alternative to conventional chemical inhibitors in corrosion prevention strategies.

Keywords

Aluminium alloy Corrosion Inhibition Millet extract Optimisation Industrial growth

(1)

Fayomi, O. S.; Ogbuozobe, O. G.; Min, H. S. Evaluation of Millet Extract As Green Inhibitor for AA6063 Corrosion in 1 M KCl: From Electrochemical Studies to Optimisation. ajc 2026, 38, 1439-1446.

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References

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References

E.S.M. Sherif, I.A. Alnaser and A.T. Abbas, Sci. Eng. Compos. Mater., 31, 20240031 (2024); https://doi.org/10.1515/secm-2024-0031

A. Dashti, M.H. Shaeri, R. Taghiabadi, F. Djavanroodi, F.V. Ghazvini and H. Javadi, Materials, 11, 2419 (2018); https://doi.org/10.3390/ma11122419

D. Prabhu and P. Rao, Int. J. Corros., 2013, 945143 (2013); https://doi.org/10.1155/2013/945143

P. Kwolek, K. Dychtoń, B. Kościelniak, A. Obłój, A. Podborska and M. Wojnicki, Metals, 12, 250 (2022); https://doi.org/10.3390/met12020250

A. Rotibi, K. Adesina and S. Abegunde, World J. Adv. Eng. Technol. Sci., 6, 40 (2022); https://doi.org/10.30574/wjaets.2022.6.1.0063

N. Raghavendra and J.I. Bhat, Period. Polytech. Chem. Eng., 62, 351 (2018); https://doi.org/10.3311/PPch.10686

A. Kumar and A. Thakur, Overview of the Properties, Applicability, and Recent Advancements of Some Natural Products used as Potential Inhibitors in Various Corrosive Systems. In: Handbook of Research on Corrosion Sciences and Engineering, IGI Global, pp. 275-310 (2023).

J. Garg, M.N. Chiu, S. Krishnan, K. Chawla, R.K. Gupta, S.K. Boda and M.C. Gupta, Appl. Biochem. Biotechnol., 196, 1008 (2024); https://doi.org/10.1007/s12010-023-04570-2

N. Raghavendra and J.I. Bhat, J. Phys. Sci., 29, 77 (2018); https://doi.org/10.21315/jps2018.29.1.6

O. Sanni, J. Ren and T C. Jen, Exploring the Potential Role of Prunus domestica in Corrosion Inhibition of AA6063-T5 Aluminium Alloy in Sodium Chloride Media, In: ASME International Mechanical Engin-eering Congress and Exposition, 86656, p. V003T03A030 (2022).

S. Mustapha, R. Elabor, A.T. Amigun, A.A. Olajire, O.O. Joseph and A.A. Faremi, Phytochemicals/Plant Extracts as Corrosion Inhibitors for Zinc in Various Electrolytes. In: Phytochemistry in Corrosion Science, CRC Press, pp. 263-295 (2024).

E.M.S. Hassani, R. Salim, E. Ech-chihbi, H. Zarrok, M. Ebn Touhami and A. Dafali, Sci. Rep., 15, 12164 (2025); https://doi.org/10.1038/s41598-025-93419-1

I.A.W. Ma, S. Ammar, S.S.A. Kumar, K. Ramesh and S. Ramesh, J. Coat. Technol. Res., 19, 241 (2022); https://doi.org/10.1007/s11998-021-00547-0

Z. Aribou, M. Ouakki, F. El Hajri, E. Ech-chihbi, I. Saber, Z. Benzekri, S. Boukhris, M.K. Al-Sadoon, M. Galai, J. Charafeddine and M. Ebn Touhami, Int. J. Electrochem. Sci., 19, 100788 (2024); https://doi.org/10.1016/j.ijoes.2024.100788

L. Chahir, F. Benhiba, N. Abad, M. El Azzouzi, H. Zarrok, M. Ebn Touhami and A. Dafali, J. Electrochem. Sci. Eng., 14, 275 (2024); https://doi.org/10.5599/jese.2177

Y. Li, Z. Bai, L. Xing, X. Zhang, Y. Wang and J. Zhang, Appl. Sci., 14, 2350 (2024); https://doi.org/10.3390/app14062350

L. Guo, M. Zhu, Z. He, Y. Wang, X. Zhang and J. Li, Langmuir, 38, 3984 (2022); https://doi.org/10.1021/acs.langmuir.1c03289

M.A. Deyab, Q. Mohsen, E. Bloise, M.R. Lazzoi and G. Mele, Sci. Rep., 12, 7579 (2022); https://doi.org/10.1038/s41598-022-11598-7

J. Li, Z. Xu, Y. Li, X. Wang, H. Zhang and Y. Wang, J. Mater. Sci., 56, 8689 (2021); https://doi.org/10.1007/s10853-020-05733-w

S. Kalam, S.A. Abu-Khamsin, M.S. Kamal and S. Patil, ACS Omega, 6, 32342 (2021); https://doi.org/10.1021/acsomega.1c04661

M. Vigdorowitsch, A. Pchelintsev, L. Tsygankova and E. Tanygina, Appl. Sci., 11, 1 (2021); https://doi.org/10.3390/app11178078

A. Abin-Bazaine, A.C. Trujillo and M. Olmos-Marquez, in eds.: M. Ince and O.K. Ince, Adsorption Isotherms: Enlightenment of the Phenomenon of Adsorption, In: Wastewater Treatment, IntechOpen (2022); https://doi.org/10.5772/intechopen.104260

Author biographies is not available.