Abstract: A polarographic electrochemical cell for the measurement of oxygen in ppb. The cathode in the system is a non-depleting carbon polytetrafluoroethylene electrode catalytically specific for oxygen reduction. The anode is a composite nickel matrix. The reaction at the anode is an electrochemical oxidation reaction but there are no soluble byproducts that contaminate the electrode. The reaction at the anode is a simple oxidation, state-of-change of the nickel in the nickel composite matrix.

Abstract: An oxygen sensor for measuring oxygen in the ppb range. The sensor comprises an electrochemical cell. The oxygen is metered to the cathode based on gaseous phase diffusion to provide a measurement proportional to volumetric concentration. Hydrogen is metered to the anode in an amount in excess of the oxygen being reduced at the cathode. A current is generated which is linear to the volumetric concentration of the oxygen in the sample gas. The concentration of the oxygen is measured based on the current generated.

Abstract: An oxygen sensor for measuring oxygen in the ppb range. The sensor comprises an electrochemical cell. The oxygen is metered to the cathode based on gaseous phase diffusion to provide a measurement proportional to volumetric concentration. Hydrogen is metered to the anode in an amount in excess of the oxygen being reduced at the cathode. A current is generated which is linear to the volumetric concentration of the oxygen in the sample gas. The concentration of the oxygen is measured based on current generated.

Abstract: A reservoir of electrolyte is placed in communication with the electrolyte of an electrochemical or electrolytic cell which is adapted for oxygen analysis. A cathode is placed in the electrochemical cell and an anode is placed in the reservoir, with a potential of 1.5 VDC applied between them. At the cathode a mild electrolysis of water occurs and a film of highly reactive hydrogen is generated. Similarly, oxygen is generated at the anode. The equilibrium partial pressure of the dissolved oxygen in the electrolyte of the electrochemical or electrolytic cell is reduced via its consumption in the reaction with the hydrogen to form water. Oxygen generated in the reservoir is allowed to effervesce. Thus, an electrolyte devoid of dissolved oxygen can be maintained which allows an accurate analysis of the gaseous sample stream.