Inhibitions imposed by kinetic constraints of membranes in all-solid-state ion-selective electrodes: characteristics of interfacial capacitances in solid contacts

Abstract

Although various materials as solid contacts have been extensive studied in all-solid-state ion-selective electrodes, there is still a lack in the study regarding kinetic phenomena at solid-solid and solid-liquid interfaces. This may lead to confusion between the performance of capacitors and that of electrical analysis systems, then finally misjudge material properties. While there are established methodologies for investigating capacitive mechanisms, they all center on the energy storage properties of particular materials and lack the capability to analyze real detected systems involving membranes. This study proposed an algorithm to investigate electrode interfaces with complex structures and uncovered the impact of membranes on the capacitance of solid contacts through experimental data and simulations. The electrochemical impedance spectroscopy is clustered using a machine learning algorithm and then distribution of relaxation time analysis is utilized to simulate results and generate multiple models of electrode interfaces. The step potential electrochemical spectroscopy is simulated based on the electrode interface model to quantitatively analyze specific charge storage processes. Simulated results revealed that the symmetry of primary charge processes under varying overpotentials for different solid contacts is proportional to the conversion ratios of each material’s capacitance, which is attributed to the Inhibition on electrode interfaces of ion-selective membranes. This work highlights the importance of considering interactions between membranes and materials in the development of transduction materials and can also be extended to investigate electrode interfaces not merely all-solid-state ion-selective electrodes.