Fabrication of composite scanning micro pH electrode and its application in localized corrosion
- 化学化工－已发表论文 
A novel composite scanning micro pH electrode was fabricated. The lrO(x)-pH electrode produced in a carbonate melt exhibited high stability, a fast potential response and ideal Nernstian response. The slope of the electrode at 15 degreesC was 56. 8 mV/pH, which was very close to the theoretical value. The 90% potential response time for a pH change from 1. 75 to 13. 90 was less than 0. 5 s. The composite scanning micro pH electrode is a promising apparatus for detecting the pH distribution on metal/solution interface. pH image on the surface of Al/Cu galvanic couple showed that both the anodic and cathodic areas could be sensed well. Localized corrosion took place on the interface of Al/Cu couple. The localized corrosion developed with time and pH value around the pitting decreased gradually.