Selective Fluoride Electrode Mechanism Studies

Abstract

We wanted to determine the mechanism of charge transport through the LaF₃ crystal in Orion's 94-09 and 94-09A fluoride electrodes. Voltage was applied to the electrode while it was in 15% Sodium Acetate Solution (pH 6.3) with or without (F¹⁸). We concluded that the mechanism of conduction through LaF₃ was one of ionic diffusion. F¹⁸ accumulated on the electrode surface very rapidly. Diffusion into the body of the LaF₃ (deeper than 300 Å) was also very rapid.