I am looking for a cheap oxygen sensor for application in a gas analysis system. The cheapest I can find is a Zirconium based car exhaust sensors, which require extremely high operating temperatures to produce significant output voltages, approximately 600 degrees centigrades. I am looking to enclose it in a plastic container, but the very large operating temperature is worrying me. Have any of you dealt with such a sensor? If so, do you think it's heat isolated enough for my application, to be enclosed within a plastic container? This is an example of a sensor I was thinking of.
I have never tried using one in a plastic container, but the body is made of metal so heat transfers relatively well. After a flame test or testing plugged into an actual exhaust I made sure to not touch the sensor with my bare fingers.
A generic plastic container will almost certainly not be able to deal with the hot operating temperatures, especially if you have to rely at all on the exhaust to heat up the sensor.
Depending on the application, you could try getting exhaust tubing with an O2 sensor port and flow your gas through the tubing past your sensor. The tubing is relatively cheap to get, you may even be able to find something at a local junk yard.
Did you look into these: http://alphasense.com/industrial-sensors/pdf/O2A1.pdf ? The form factor is common to several manufacturers.
You will need some analog circuit to interface it to an ADC.