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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 anodic behaviour of zinc was investigated in ethanol solution containing LiCl and water. Zinc was polarised by using cyclic voltammetry and chronoamperometry techniques. During the course of the dissolution of zinc, a colloidal suspension of ZnO nanoparticles was obtained in 0.1 M LiCl/ethanol solutions that contain H 2 O. The suspension is formed only if water is present, and the rate of the process depends on the water content. Moreover, the concentration

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This work for the first time evaluates the ability of homogeneous, stable, and very pure zinc oxide nanoparticles (ZnONPs-GS) synthesized by the "green chemistry" - an environmentally friendly, cheap, and...