Exploring metasequoia glyptostroboides leaf extract as an eco-friendly corrosion inhibitor for Q235 steel

This study demonstrates the excellent capability of Metasequoia glyptostroboides leaf extracts to act as effective and eco-friendly corrosion inhibitors for Q235 mild steel surfaces across simulated 1 M hydrochloric acid conditions, attributable to diverse terpenoid and polyphenolic phytochemicals. Gas chromatographic profiling indicated multiple bioactive compounds including 13.92% camphene, 15.59% naringenin and 9.12% trans-caryophyllene. Weight loss analysis showed 500 ppm optimal extract concentration attaining 83.62% inhibition. Potentiodynamic scans revealed predominately anodic control with corrosion currents reducing from 432 to 92 μA/cm2 alongside enhanced polarization resistances from 19.7 to 132 Ω/cm2 substantiate surface protective film depositions. FTIR and UV-Vis spectroscopy indicates chelating flavonoids aid inhibition through iron complexation. SEM micrographs displayed smoother substrate morphology versus cracked unmodified surfaces while atomic force metrology reduced roughness from 853 nm to 352 nm. Incremental EDX nitrogen peaks and contact angle escalations from 36° to 72° further supplements molecular adsorption phenomena. Remarkable performance retention even at higher temperatures above 50% at 338 K and detailed mechanistic interpretations conclusively verify Metasequoia's candidature as abundant natural sources for sustainable anticorrosion formulations across industrial usage contexts.