Communication—The pH Detection of Magnesium Dissolution during Anodic Polarization with Channel Flow Double Electrode

Abstract

A pH sensing channel flow double electrode was developed for pH detection of magnesium dissolution during anodic polarization. Because the hydroxide ions generated during the anodic polarization of a magnesium working electrode (Mg-WE) flow to a tungsten pH sensor (W-pH) downstream of the Mg-WE, pH changes can be detected by measuring the rest potential of the W-pH. A video recording of the Mg-WE surface was performed during the measurement, indicating that increase of pH was related to the film breakdown on Mg-WE surface. The hydrogen evolution rate of the order of 10 −8 mol cm −2 s −1 was estimated from pH values.

Detection of Hydrogen Gas Generated upon Magnesium Dissolution Using a Gas Chromatograph–Channel Flow Electrode System

“…5 Because the pH of the electrolyte increases owing to the Mg dissolution during these measurements, it is difficult to investigate the effect of electrolyte pH on HE efficiencies of Mg dissolution, which critically affects battery performance. 10 In this study, we developed an in situ gas detection system comprising a channel flow electrode (CFE) [11][12][13] and gas chromatograph. In this system, a gas-liquid separator tank, which was placed downstream of the channel flow cell, was connected to the gas chromatograph.…”

Communication—In Situ Hydrogen Evolution Detection from Mg Electrode During Anodic Potentiodynamic Polarization Measurement with Gas-Chromatographic Analysis

“…Toward wider industrial applications of Mg and its alloys, various real-time hydrogen (H 2 ) gas analysis methods have been developed [2][3][4][5][6][7][8][9] and demonstrated real-time measurements of cathodic currents related to the HE of Mg during potentiodynamic and galvanodynamic polarizations. 2,4 Curioni 2 developed a H 2 volume collection system based on the buoyant forces exerted by the gas upon accumulation in a submerged container.…”