Gold or platinum films deposited on a Nation membrane were used to measure surface conductance of the membrane. Acidic gases such as HCl or S02, Introduced as mixtures with an Inert gas, were found to affect the conductance of the membrane surface facing this mixture while the other side of the membrane was constantly supplied with a moist inert gas. The relative conductance (G/G0) Is most affected within the 0–0.5 and 3–4.5 vol % ranges both for HCl and S02. The effect Is higher for the Pt-deposlted than it Is for the gold-deposited membrane: for an HCl concentration of 1.5 vol %, G/G0 Is 5 for Pt deposited on Nation while it Is only 1.3 for gold deposited on Nation. This Is attributed to different geometries and porosity of the Pt and Au electrodes. No conductance response was observed for C02 which yields with water a much weaker acid than those formed by HCl and S02.
ASJC Scopus subject areas
- Analytical Chemistry