Influence of crystallographic properties on antimony electrode potential—III. Oriented monocrystalline material

Abstract

Crystallographically oriented monocrystalline antimony electrodes representing close-packed crystallographic planes have been studied in HClSbOCl solutions at pH 1.9. The electrode potentials were found to stabilize in less than 1 min. They then remained stable at that level to within 1 mV for more than 100 h of continuous use unless a surface defect existed or developed. The potentials of the different electrodes were reproducible to within 1 mV and repeatable to within 0.2mV. The typical short-term potential variations were 0.1 mV for long periods of time and no stirring effect was noted during the first 100h of use. All electrodes responded reproducibly to oxygen and nitrogen bubbling and to temperature changes in the solution. The maximum long-term potential drift encountered after the first 100 h period of relative potential stability was − 0.8mV/day during a total of 800 h use. Sem studies of the surfaces of used electrodes showed only minor corrosion and no signs of a covering surface (oxide) structure. The surfaces also appeared less corroded for electrodes with more close-packed surfaces. These electrodes also possessed the most negative potentials.