Investigations into the development of an alternative concept of a potentiometric CO_2 sensor

摘要

Potentiometric measurements were carried out with various types of solid electrolyte galvanicv cels that operate as an oxygen concentration chaina nd use an alkali carbonate in equilibrium with O_2 and CO_2 as main component of the gas sensitive electrode. It turns out that the feasibility of such a kind of a CO_2 sensor strongly depends on the material that hosts the substance acting as an intermediator between the chemical potential of the alkali metal, resulting from the carbonate, and the oxygen potential. The best sensor properties were obtained by a cell in which an electronically short-circuited phase mixture of Na-(#beta#+#beta#")-Al_2O_3 is utilized as an interlayer between the oxygen ion conducting solid electrolyte and the gas sensitive carbonate layer.