Abstract: The inhibition effect of Yushania polytricha leaves extract(YPLE) on the corrosion of aluminum in 1.0 mol/L HCl media was studied by mass loss, potentiodynamic polarization curves, electrochemical impedance spectroscopy, Fourier transform infrared spectroscopy, ultraviolet spectrophotometry and scanning electron microscope methods. The results show that YPLE is a good inhibitor, and the inhibition efficiency increases with the inhibitor concentration. The adsorption of YPLE on aluminum surface obeys Langmuir adsorption isotherm. YPLE behaves as a cathodic inhibitor. EIS spectra exhibit one capacitive loop at high frequencies followed by an inductive one at low frequency values, and the impedance value increases with the inhibitor concentration. SEM results confirm the corrosion of aluminum is retarded remarkably by the addition of YPLE.

Key words: Aluminum, hydrochloric acid, Yushania polytricha, extract, inhibition, adsorption