The Interface Characterization of 2-Mercapto-1-methylimidazole Corrosion Inhibitor on Brass

This work presents a detailed surface analytical study and characterization, with an emphasis on the X-ray photoelectron spectroscopy (XPS) time-of-flight secondary ion mass spectrometry (ToF-SIMS) analyses of 2‑mercapto‑1‑methylimidazole (MMI) as corrosion inhibitor for brass. First, electrochemical measurements demonstrated inhibition effect MMI in 3 wt.% NaCl solution. Next, formation layer its properties after 1 month immersion was analyzed attenuated total reflectance–Fourier-transform infrared spectroscopy, atomic force microscopy, field-emission scanning electron contact angle analysis. Moreover, to gradually remove organic layer, gas cluster beam (GCIB) sputtering source at different accelerated voltages sizes employed. After each cycle, high-resolution XPS analysis performed. angle‑resolved carried out MMI-treated brass sample analyze heterogeneous layered structure (the interface organic/inorganic substrate). The were also investigated detail using ToF-SIMS spectra 2D imaging. Special attention devoted possible spectral interferences MMI‑related species. thermal stability MMI-related species molecular-specific signals without determined by performing cooling/heating experiment associated measurements. It shown that these desorbed from temperature range 310–370 °C.