Electrochemical Examination of the Influence of H_2SeO_3 on Molybdenum Electrodeposition on Tin Oxide Electrode from Aqueous Citrate Electrolyte

摘要

Cyclic voltammetry and chronoamperometry have been used to evaluate the electrochemical reactions taking place under SnO_2/glass electrode polarization in a solution of Na_2MoO_4,H_2SeO_3,sodium citrate (C_6H_5Na_3O_7) and in solutions consisting of their mixtures.According to our study,the presence of a small concentration of H_2SeO_3 in the electrolyte is necessary to induce the reduction of MoO_4~(2-) ions.Experimental data support an assumption that the reduction of MoO_4~(2-) ions to molybdenum could occur when selenium nuclei are initially formed on the electrode.Eventually selenium nuclei induce the electrodeposition of molybdenum,giving finally thin Mo-Se film layers.AAS analysis confirms that in the potential interval between-1.0 and-1.2 V,thin films with a Mo/Se atomic ratio 0.63 and 0.57,respectively,are obtained.