MQ-9, MQ-9 gas sensor, MQ-9 Datasheet, MQ-9 Pinout, MQ-9 Working, MQ-9 Features Hi seekers! Welcome to another article discussing a sensor from the MQ gas sensor series. Today, we are discussing the MQ-9 gas sensor, which can detect gases like carbon monoxide, CH4, and LPG. It has a long life and a simple structure, and the heart of this gas sensor is the sensing element on the ...