The focus of this research is on the development of a gas sensor toolkit for sensitive, selective and stable detection of undesirable gas species (e.g. NOx, SOx, CO, CO2) at high-temperatures. In2O3, NiO, Ga2O3 and Y-doped BaZrO3 for the detection of NOx, H2, CO and humidity, respectively have been investigated. Of primary importance were the effects of materials processing conditions on the gas sensitivity and response rate. Design, fabrication and integration of microhotplate structures with gas sensitive layers capable of functioning at temperatures greater than 500 °C were also performed.

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Thank you sir for ur answer & ur valuable time @ Prem Baboo.

It depends on what type of gas. For example, it the gas flammable or non-flammable?

In any case, the simplest and cheapest gas sensor is the catalytic bead sensor. You can readily buy this sensor for the specific gas of interest to you.

Hope this helps answer your question.

Professor Yehia Khalil

Yale University

USA

Thank you Professor Yehia Khalil