Green synthesis of zinc oxide nanoparticles using Clutia pulchella (lightning bush) extract: characterization and corrosion inhibition performance

Abstract Nanostructured coatings offer exceptional physicochemical properties that extend beyond the capabilities of conventional materials, enabling their use in diverse industrial applications. In this study, zinc oxide nanoparticles (ZnO NPs) were synthesized via an eco-friendly, plant-mediated approach using Clutia pulchella leaf extract and their effectiveness as corrosion inhibitors for carbon steel in 0.5 M HCl was investigated. The synthesis was optimized by systematically varying precursor concentration, pH, temperature, reaction time and extract dosage to achieve well-defined, high-quality nanoparticles. The obtained nanoparticles were characterized by UV–Vis, FTIR, XRD, SEM–EDS, DLS and zeta potential analyses, confirming the formation of crystalline ZnO with nanoscale crystallite size and good colloidal stability. The effectiveness of ZnO nanoparticles in inhibiting corrosion was evaluated through various approaches, including measuring weight loss, using potentiodynamic polarization and electrochemical impedance spectroscopy. The NPs provided up to 90% inhibition efficiency as they formed a protective film on the surface, limiting interaction between the metal and the acidic environment. This suggests that green synthesized ZnO NPs may provide a sustainable and efficient alternative to traditional corrosion inhibitors, thus promoting the development of environmentally friendly industrial practices.