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Electrochemical gold deposition from sulfite solutions was studied by means of voltammetry, EIS and EQCM. A gold film electrode was used for polyaniline layer formation by electrochemical oxidation of aniline. The standard electrochemical reduction potential of the reaction [Au(SO 3 ) 2 ] 3-+ e -= Au + 2 SO 3 2-was determined, and is equal to 0.116 V (vs. NHE). Both solution stirring and temperature increase accelerate the electrochemical reduction of gold, when the electrode potential is below -0.55 V. When the potential is above -0.55 V the electrochemical reduction proceeds via passive layer formation. Our study suggests that the passive layer consists of chemically adsorbed sulfite ions and sulfur. The gold film deposited from sulfite solution is a high quality substrate suitable for conducting polymer layer formation. This technique, where a polymer layer electrode is prepared by thin gold film deposition onto a metal surface and by subsequent polymer layer formation, can be applied in sensor research and technology.

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Cadmium tin oxide (CTO) films on glass substrates were synthesized and functionalized by octadecyltrichlorosilane (OTS). CTO films were transparent with the bandgap of 2.92 eV. They exhibited n-type conductivity and carrier concentration of (3.31 ± 0.38) · 1019 cm−3. Weak temperature dependence points out to a nearly degenerative state of the carriers in the CTO films. Silanization by OTS yielded hydrophobic surface with the contact angle values reaching 103 ± 12 degrees. Silanization of films was followed by a significant reduction of the interfacial capacitance, which upon completion of the functionalization reached levels below 3 μF cm−2. The value of the electric capacitance as well as data of ATIR absorption, hints at sparse and disordered coverage of the CTO surface by octadecylalkylsilane molecules. Such organic layer, however, was able to trigger phospholipid (60% dioleoylphosphocholine and 40% cholesterol) vesicle rupture and the formation of a secondary layer of phospholipid, thus rendering hybrid bilayer surface construct. Such hybrid constructs may be useful in applications where electrode coupling to a model biological membranes and membrane bound proteins is required, such as biosensing and photovoltaics.

The cyanide-containing effluents are dangerous ecological hazards and must be treated before discharging into the environment. Anodic oxidation is one of the best ways to degrade cyanides. Pt anodes as the most efficient material for the cyanide electrochemical degradation are widely used. However, these electrodes are too expensive for industrial purposes. In this work Ti electrodes covered with nano-sized Pt particle layer were prepared and used for the anodic oxidation of cyanide ions. Surface images of Ti electrodes and Ti electrodes covered with different thickness layer of Pt were compared and characterized by the atomic force microscopy (AFM). The products formed in the solution during the CNions electrooxidation were examined by the Raman spectroscopy. An electrochemical Fast Fourier transformation (FFT) impedance spectroscopy was used to estimate the parameters that reflect real surface roughness of Pt-modified Ti electrodes.