Sensitive material of the MQ-9 gas sensor is SnO2, which has lower conductivity in clean air. It make
detection by method of cycle high and low temperature, and detect CO when low temperature (heated
by 1.5V). The sensor’s conductivity is higher along with the gas concentration rising. When high
temperature (heated by 5.0V), it detects Methane, Propane etc combustible gas and cleans the other
gases adsorbed under low temperature. Please use simple electrocircuit, Convert change of conductivity
to correspond to the output signal of gas concentration.
MQ-9 gas sensor has high sensitivity to Carbon Monoxide, Methane and LPG. The sensor could be
used to detect different gases contains CO and combustible gases, it is with low cost and suitable for
different applications.

Features:

Good sensitivity to CO/Combustible gas
High sensitivity to Methane, Propane and CO
Long life and low cost
Simple drive circuit

Application:

Domestic gas leakage detector
Industrial gas detector
Portable gas detector