ИСТИНА

Some 3-amino-1,2,4-triazoles (ATA) with 5-R-ATA electron-accepting substitutes were found to have high adsorption energy measured by ellipsometry towards copper. They are CF3–ATA, COOH–ATA, C3H7SO2–ATA, the adsorption energy is -99.0, -90.0, -93.0 kJ/mol respectively. Anodic polarization curves taken in borate buffer solution (BBS) at pH 7.40 with 0.05 mol/l NaCl show current suppression at low and high concentrations of CF3ATA, but within range of 0.01 – 0.2 mmol/l we observed great increase of current at 200-250 mV. The first peak is due to oxidation of copper to Cu+. The second one corresponds to formation of Cu2+ that was proven by X-ray photoelectron spectroscopy (XPS) of the electrode exposed at this potential. By means of XPS it was found that all substances have different influence on copper surface composition depending on concentration after pre-determined time of immersion. Adsorption layers formed by 5-R-ATA suppose chemisorption through the atoms N1 and N2 of the azole ring, with N1 being deprotonated. The Cu(I)-inhibitor complex is formed, that is proven by changes in CuLMM Auger-spectra. The thickness of this layer reaches 2.4 nm in 1 h of immersion. Further exposition leads to formation of Cu2+ and CuLMM becomes non-informative. Protective ability of the layers was examined in salt fog chamber. The effect of other substances is widely discussed.