Gas sensor

Abstract

A gas sensor assembly is described, comprised of conductive and non-conductive plastic sections, and having a receptacle formed therein. A gas-sensing agent is disposed in the receptacle, and electrodes are positioned adjacent to the receptacle in fluid contact with the gas sensing agent. Each electrode is also in contact with a conductive plastic section of the sensor assembly. The conductive plastic sections are physically and electrically isolated from each other by a non-conductive plastic section.

1 . A gas sensor comprising: 
 a housing having a receptacle formed therein;    a gas-sensing agent disposed in the receptacle; and    a plurality of electrodes disposed in fluid contact with the gas-sensing agent,    wherein the housing has a plurality of conductive housing portions and non-conductive housing portions, each of the conductive housing portions being conductively coupled to a respective one of the electrodes, the conductive housing portions being comprised of a conductive plastic material, with at least one of the electrodes being contained wholly within the receptacle.    
   
   
       2 . The gas sensor of  claim 1 , wherein the plurality of electrodes comprises two electrodes and wherein the plurality of conductive housing portions comprises two conductive housing portions.  
   
   
       3 . A gas sensor comprising: 
 a housing having a receptacle formed therein;    a gas-sensing agent disposed in the receptacle; and    a plurality of electrodes disposed in fluid contact with the gas-sensing agent,    wherein the housing has a plurality of conductive housing portions and non-conductive housing portions, each of the conductive housing portions being conductively coupled to a respective one of the electrodes, the conductive housing portions being comprised of a conductive plastic material, with the conductive housing portions being formed around electrical wires.    
   
   
       4 . The gas sensor of  claim 3 , wherein the plurality of electrodes comprises two electrodes and wherein the plurality of conductive housing portions comprises two conductive housing portions.  
   
   
       5 . A gas sensor comprising: 
 a housing having a receptacle formed therein;    a gas-sensing agent disposed in the receptacle; and    a plurality of electrodes disposed in fluid contact with the gas-sensing agent, said electrodes comprising a liquid electrode mixture deposited on a substrate, the liquid electrode mixture comprising a polymer mixture of suspended micro- or nano-particles of fluorocarbon material, and metallic micro- or nano-particles.    
   
   
       6 . The gas sensor of  claim 5 , wherein the liquid electrode mixture further comprises one or more surfactants, emollients, or flocculants.  
   
   
       7 . The gas sensor of  claim 5 , wherein the solid polymer material comprises Teflon or other non-reactive binders, wherein other non-reactive binders comprise carbowax or methocel.  
   
   
       8 . The gas sensor of  claim 5 , wherein the metallic particles comprise platinum, gold, lead, ruthenium, or alloys thereof, or other electrochemical catalyst.  
   
   
       9 . The gas sensor of  claim 5 , wherein the electrodes result in a high reactivity for ethanol and a low reactivity for carbon monoxide.  
   
   
       10 . A liquid electrode mixture for use in a gas sensor, comprising: 
 from about 60 to about 240 milligrams of platinum black catalyst;    from about 900 to about 1100 milligrams of water;    from about 300 to about 400 microliters of 1-propanol; and    from about 100 microliters to about 150 microliters of a polymer mixture comprising from about 40% to about 80% PTFE by weight and water.    
   
   
       11 . The liquid electrode mixture of  claim 10 , further comprising one or more surfactants, emollients, or flocculants.