Noise in amperometric NO2 sensor

Nitrogen dioxide (NO₂) is a highly toxic gas harmful to the environment, which can be threat to human health even at low concentrations. To overcome limitations of standard solid NO₂ sensors based on inorganic materials, a new sensor with solid polymer electrolytes (SPE) was developed. Our study deals with investigation of fluctuation phenomena in the electrochemical NO₂ sensor, which is based on three-electrode topology and solid polymer electrolyte. Experimental result shows that generation-recombination (G-R) noise seems to be main components of current fluctuations in this sensor. The concentration of detected matter affects noise spectral density of sensor. As the concentration increases, G-R noise rises and is supposed to be connected with chemical processes on active layer of sensor. The shift of G-R component is supposed to be caused by increased flux density between active layer and environment.