Study Benzotriazole as the Oxidation-Inhibiting Protective Layer of Iron Film

WeiLi Luo^1*

¹工程與系統科學系, 國立清華大學, 新竹市, Taiwan

* Presenter:WeiLi Luo, email:jonathan.luo6405@gmail.com

Benzotriazole is an organic material that has been widely used in anti-corrosion of metals. Its main purpose is to inhibit the corrosion behavior of metal materials (e.g., copper, iron, cobalt) in the immersed state (e.g., in liquid conveying pipelines). Few cases also show that benzotriazole adsorbed on the copper surface through the vapor phase can also effectively inhibit copper corrosion. In our work, benzotriazole will be deposited on the sputtered iron film by vacuum evaporation as an oxidation-inhibiting protective layer.
X-ray absorption spectroscopy is used to verify the valence state of iron. For iron samples with benzotriazole covering about 5-30 microns as a protective layer, the K edge absorption spectrum of Fe obtained in the fluorescence mode indicates that Fe is mainly in a zero-valent state that has not been oxidized. Since the signal of the fluorescence mode comes from the bulk sample, it is believed that benzotriazole does prevent the oxidation of Fe. However, the Fe L edge absorption spectrum obtained in the total electron yield mode indicates that Fe is mainly in a positive divalent state. In comparison to a pure iron sample without a protective layer, a positive trivalent state was found. Since the total electron yield mode of running XAS at Fe L-edge is a surface-sensitive measurement way, we predict that a complex of iron and benzotriazole will form on the iron surface, just like the Fe(Ⅱ)BTA complex that is known to be formed under liquid immersion experiments. In addition, the dynamic potential polarization scanning experiment will also be used to verify the corrosion resistance of the vacuum evaporation benzotriazole film.

Keywords: Benzotriazole, Oxidation-Inhibiting, Protective Layer