ON THE QUANTITATIVE-DETERMINATION OF CARBON-DIOXIDE IN AIR - A NEW SENSOR TECHNIQUE USING ANODIC ADSORBATE STRIPPING

The formation of ''reduced CO2'' in the presence of air is studied on Pt foils and specially designed Pt gas diffusion electrodes. Potentiodynamic sweeps and, as the key technique, potential steps are used to determine the oxidation charge released during an anodic process following adsorption. The integral amount of charge is used as a quantitative measure of the CO2 partial pressure in air. The limits of sensing CO2 are shown. The sensor response is restricted to mediUM CO2 contents in air, i.e. from ca. 0.5% to 50%. Gas ratios below 0.3% CO2 cannot be measured. The new sensor is a versatile tool for environmental research and can also be used for industrial safety.