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We present a novel and facile method enabling synthesis of iron oxide nanoparticles, which are composed mainly of maghemite according to X-ray diffraction (XRD) and Mössbauer spectroscopy studies. The proposed process is realized by anodic iron polarization in deaerated LiCl solutions containing both water and ethanol. Water seems to play an important role in the synthesis. Morphology of the product was studied by means of transmission electron microscopy and XRD. In the solution containing almost 100% of water a black suspension of round shaped maghemite nanoparticles of 20–40 nm size is obtained. Regulating water concentration allows to control nanoparticle size, which is reduced to 4–6 nm for 5% of water with a possibility to reach intermediate sizes. For 3% or lower water concentration nanoparticles are of a needle-like shape and form a reddish suspension. In this case phase determination is problematic due to a small particle size with the thickness of roughly 3 nm. However, XRD studies indicate the presence of ferrihydrite. Coercivities of the materials are similar to those reported for nanoparticle magnetite powders, whereas the saturation magnetization values are considerably smaller.

The inhibition effect of gum arabic (GA) was investigated using weight loss measurements and electrochemical techniques. The results show that the inhibition efficiency of GA increased with an increase in the concentration of the inhibitor but decreased with the temperature. Immersion time was found to have a profound effect on the corrosion inhibition performance of the inhibitor. Polarization measurements revealed that GA was a mixed-type inhibitor, with higher influence on the anodic reaction. The inhibitor followed the Temkin’s adsorption isotherm, and the values of the standard free adsorption energy indicate a mixed-type adsorption, with the physical adsorption being more dominant. SEM–EDS and FT-IR measurements were also employed to support the findings.