Electrochemical gas sensor
First Claim
1. An electrochemical oxygen sensor comprising:
- a body having a cavity;
an electrolyte in said cavity;
an auxiliary electrode in contact with said electrolyte;
a sensing electrode in contact with said electrolyte;
a porous carbon blocking electrode positioned intermediate said auxiliary electrode and said sensing electrode and having a thickness of at least 0.5 cm in a direction in which said auxiliary electrode is separated from said sensing electrode, said blocking electrode reducing electroactive materials within said electrolyte; and
a reference electrode in contact with said electrolyte and positioned intermediate said auxiliary electrode and said sensing electrode, said reference electrode comprising a material including silver.
3 Assignments
0 Petitions
Accused Products
Abstract
An electrochemical gas sensor including a sensor body having a cavity, an electrolyte in the cavity, an auxiliary electrode in contact with the electrolyte, a sensing electrode in contact with the electrolyte, and a blocking electrode in contact with the electrolyte. At least a portion of the blocking electrode is positioned intermediate the auxiliary electrode and the sensing electrode, and the blocking electrode reduces electroactive materials within the electrolyte. Also disclosed is a method for sensing a partial pressure of a target gas in a sample gas, the method including introducing the sample gas into a gas sensor, applying different potentials to the auxiliary electrode, sensing electrode and blocking electrode, reducing electroactive materials present in the electrolyte to prevent the electroactive materials from contacting the sensing electrode, and outputting an electrical signal from the gas sensor representative of the target gas partial pressure.
46 Citations
20 Claims
-
1. An electrochemical oxygen sensor comprising:
-
a body having a cavity;
an electrolyte in said cavity;
an auxiliary electrode in contact with said electrolyte;
a sensing electrode in contact with said electrolyte;
a porous carbon blocking electrode positioned intermediate said auxiliary electrode and said sensing electrode and having a thickness of at least 0.5 cm in a direction in which said auxiliary electrode is separated from said sensing electrode, said blocking electrode reducing electroactive materials within said electrolyte; and
a reference electrode in contact with said electrolyte and positioned intermediate said auxiliary electrode and said sensing electrode, said reference electrode comprising a material including silver. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17)
-
-
18. An oxygen sensor comprising:
-
a body having a cavity;
an electrolyte in said cavity;
a sensing electrode, in contact with said electrolyte, reducing oxygen at said sensing electrode to produce hydroxyl ions;
an auxiliary electrode, in contact with said electrolyte, oxidizing hydroxyl ions;
a porous carbon blocking electrode in contact with said electrolyte, at least a portion of said blocking electrode positioned intermediate said auxiliary electrode and said sensing electrode, wherein said blocking electrode has a thickness of at least 0.5 cm in a direction in which said auxiliary electrode is separated from said sensing electrode, said blocking electrode reducing electroactive materials within said electrolyte; and
a reference electrode in contact with said electrolyte and positioned intermediate said auxiliary electrode and said sensing electrode, said reference electrode comprising a material including silver.
-
-
19. An electrochemical gas sensor for sensing a partial pressure of oxygen in a sample gas, the electrochemical gas sensor comprising:
-
a sensor body having a cavity and a vent;
an electrolyte disposed in said cavity of said sensor body;
a sensing electrode, mounted on said sensor body and in contact with said electrolyte, said sensing electrode reducing oxygen to produce hydroxyl ions;
an auxiliary electrode mounted on said sensor body and in contact with said electrolyte, said auxiliary electrode oxidizing hydroxyl ions;
a porous carbon blocking electrode mounted on said sensor body, at least a portion of said blocking electrode positioned intermediate said sensing electrode and said auxiliary electrode and having a thickness of at least 0.5 cm in a direction in which said auxiliary electrode is separated from said sensing electrode, said blocking electrode reducing electroactive materials that contact said blocking electrode;
a reference electrode mounted on said sensor body and positioned intermediate said auxiliary electrode and said sensing electrode, said reference electrode controlling a potential at said sensing electrode and providing an electrical reference for said blocking electrode and said reference electrode comprising a material including silver;
a circuit generating an output through said sensing electrode; and
a circuit generating an output through said blocking electrode.
-
-
20. An electrochemical gas sensor for sensing a partial pressure of oxygen in a sample gas, the electrochemical gas sensor comprising:
-
means for introducing the sample gas to the electrochemical gas sensor;
an auxiliary electrode mounted on the electrochemical gas sensor;
means for applying electrical potential to said auxiliary electrode;
a sensing electrode mounted on the electrochemical gas sensor;
an electrolyte contained within the electrochemical gas sensor;
a porous carbon blocking electrode positioned intermediate said auxiliary electrode and said sensing electrode and having a thickness of at least 0.5 cm in a direction in which said auxiliary electrode is separated from said sensing electrode, for reducing electroactive materials present in said electrolyte;
a reference electrode in contact with said electrolyte and positioned intermediate said auxiliary electrode and said sensing electrode, said reference electrode comprising a material including silver; and
means for outputting an electrical signal from the gas sensor representative of the target gas partial pressure.
-
Specification