Potentiostatic and impedance spectroscopic studies of the anodic behavior of cobalt silicides in fluoride-containing acidic solutions

摘要

The anodic behavior of cobalt silicides Co2Si and CoSi2 in solutions x M H2SO4 + y M HF at the potentials E from -0.22 to 2.0 V (SHE) has been studied by the methods of polarization measurements and impedance spectroscopy. At 0.5 < E < 1.5 V, the reaction order with respect to HF is about 1 for Co2Si and about 2 for CoSi2. For Co2Si electrode the characteristic frequencies were determined from impedance spectra as a function of E, HF and H2SO4 concentrations. On this basis the mechanisms of anodic processes on Co2Si are discussed.