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Документ Studying the kinetics of electrode reactions on copper, silver and gold in acid thiourea-citrate electrolytes(2019) Smirnova, O. L.; Brovin, A. Yu.; Pilipenko, A. I.; Zhelavska, Yu. A.The kinetics of electrode reactions that take place on copper, silver and gold electrode in acid thiourea-citrate electrolytes has been studied. It is established that the anodic dissolution of metals is accompanied by the formation of stable thiourea metal complexes of a cation-type complex. The citric acid provides the acidic pH-value of the solutions and contributes to the active dissolution of anodes. The ionization rate is limited by the diffusion of charged particles into the electrolyte volume. The cathode reduction of metals obeys the mechanisms of mixed kinetics that includes the diffusion and the preceding chemical complexes dissociation reaction. The charge of the complex ions of copper, silver and gold is +1. Therefore, their dissolution at the anode and reduction at the cathode occurs with the maximum possible electrochemical equivalent.Документ Study of anode processes during development of the new complex thiocarbamide-citrate copper plating electrolyte(Технологический центр, 2018) Smirnova, Olha; Pilipenko, Alexei; Pancheva, Hanna; Zhelavskyi, Alexei; Rutkovska, KaterynaThe kinetics of anodic reactions occurring on copper in thiocarbamide-citrate solutions was studied. Thiocarbamide forms stable copper (I) complexes of the cationic type with a coordination number equal to unity. Citric acid ensures acid pH value of electrolyte and causes active dissolution of copper under conditions of anode polarization. The joint presence of CS(NH₂)₂ and C₆H₈O₇ in the solution contributes to the copper electrode activation under conditions of anodic polarization. Increasing the concentration of thiocarbamide leads to a drastic shift of copper dissolution potentials towards the region of negative values. Study of the kinetics of anodic behavior of copper by acquiring the voltammograms revealed the nature of the limiting stage of reaction. It is shown that the process of dissolution in a thiocarbamide-citrate electrolyte is controlled by the diffusion phase. This is confirmed by the results of graphical processing of polarization dependences in coordinates η–lg(1–ja/jd). An increase in υр within 5‒100 mV·s⁻¹ causes an increase in jd from 2.2 to 12.0 mА·cm⁻², which indicates diffusion control over the process. The process of copper dissolution proceeds under stationary mode with uniform etching of intragrain boundaries and volume of the metal's grain.