Characteristics of the SEI-Layer Formations on the Bi2Se3 Anode in LiNO3 and NaNO3 Solutions by Electrochemical Impedance Spectroscopy

Dissolved O-2 and CO2 in aqueous electrolytes lead to the formation of oxides and carbonates on the electrode surface. The formation of the SEI layer on the Bi2Se3 anode was investigated by cyclic voltammetry and EIS methods. The SEI layer on the surface of the Bi2Se3 anode, in addition to soluble carbonates and oxides, also includes water- insoluble (BiO)(2)CO3. The composition and concentration of the electrolyte affect the electrochemical characteristics of the formed SEI layer. During cycling the resistance and capacitance of the SEI layer gradually decreased for both LiNO3 and NaNO3 which showed the instability in the SEI layer and the dissolving of soluble components.