Sensitive material of MQ137 gas sensor is SnO2, which
with lower conductivity in clean air. When the target combustible gas exist,
The sensor’s conductivity is more higher along with the gas concentration
rising. Please use simple electrocircuit, Convert change of conductivity to
correspond output signal of gas concentration.
gas sensor has high sensitity to Ammonia, also to other organic amine. The
sensor could be used to detect different gas which contains Ammonia, it is with
low cost and suitable for different application.