Zn(Ta1-xNbx)2O6 nanomaterials. Synthesis, characterization and corrosion behaviour

Abstract

Zn(Ta1-xNbx)2O6 pseudo-binary oxide nanocrystalline materials (where x = 1; 0.5; 0.1; 0.05 and 0) were obtained through a solid-state method and characterized by X-ray diffraction (XRD) analysis, Fourier Transform infrared (FTIR) spectroscopy and ultraviolet-visible (UV-Vis) spectroscopy. In addition, their morphology and topography were determined by field emission-scanning electron microscopy (SEM) and atomic force microscopy (AFM). There was a significant dependence between the rugosity and the uniformity of the crystals. Crystals evenly organized in multilayers had the lowest values of rugosity and non-uniform fractal type architectures had the highest values of rugosity. The anti-corrosion features of the compounds were evaluated after deposition on carbon steel (OL) in 0.1 M Na2SO4 media by open circuit potential measurements and the potentiodynamic polarization technique with Tafel representation. The inhibition efficiency of the pseudo-binary oxides deposited on a carbon steel electrode was in the range 42.3–52.7 %, which was promising for their further multiple-layer deposition with porphyrins in order to improve anticorrosion properties. Due to the high band gap (3.80–4.30 eV), provided by increasing the tantalum content, four of these pseudo-binary oxides could find applications in photovoltaic cells.