Study of the Electrochemical Oxygen Intercalation into Thin Amorphous Films of Ln_2NiO_(4+delta) (Ln=La,Pr,Nd) with EQCM and EIS

摘要

Mixed oxides described by the formula Ln_2NiO_(4+delta) (Ln:La,Pr,Nd) are candidate materials for applications in sensors and other electronic components.Excess oxygen can be inserted into their lattices (8 up to 0.25),which changes the electronic and magnetic properties.In contrast to gas phase equilibria,the intercalation process may be performed electrochemically at room temperature.The objective of this study is to determine the degree and the kinetics of the electrochemical oxygen intercalation into thin films of Ln_2NiO_(4+delta) and to clarify the oxygen transport mechanisms,applying the electrochemical quartz crystal microbalance (EQCM) technique.Changes in some of the material properties caused by the intercalation reaction are characterized by electrochemical impedance spectroscopy (EIS).