Quartz crystal micro-balance trace ammonia gas detection device

The invention discloses a quartz crystal micro-balance trace ammonia gas detection device, comprising a sensitive quartz crystal microbalance (QCM) sensor and a reference QCM sensor, which are respectively connected with a crystal oscillation circuit A and a crystal oscillation circuit B, wherein signal output ends of the crystal oscillation circuit A and the crystal oscillation circuit B are respectively connected with a frequency measurement circuit A and a frequency measurement circuit B, also connected with a personal computer (PC) machine with a built-in Labview data acquisition process program by a frequency differential circuit and a data acquisition card; and the sensitive QCM sensor is a quartz crystal oscillator coated with a sensitive coating on the surface. The sensitivity degree of the quartz crystal micro-balance trace ammonia gas detection device is high, the precision and range of the frequency measurement are increased by using the frequency measurement circuit way combining a single-chip microcomputer with a complex programmable logic device (CPLD); the sensitivity degree of the quartz crystal micro-balance trace ammonia gas detection device is less affected by environment; the selectivity is good; and the produced polyaniline film has single absorption of the ammonia gas and is less susceptible to other gas interference.