The research of the ozone electrochemical sensors for compact portable indicator/meter of ozone concentration

Abstract

To measure the concentration of ozone in the work zone and for control its maximum allowable concentration is most suitable, compact portable indicator/meter concentration of ozone. As a sensitive element is advisable to use in them electrochemical ozone sensors.Electrochemical ozone sensors of amperometric type with two electrodes were designed and manufactured in the National Technical University of Ukraine “Igor Sikorsky Kyiv Polytechnic Institute”.Sensitivity, linearity characteristics of transformation and time of conversion are main metrological parameters of electrochemical ozone sensors. These characteristics were studied during the tests for two types of electrochemical ozone sensors: on the basis of solid and liquid electrolyte.Research the characteristics of sensors was conducted for different denominations load resistor, namely: R = 50, 100, 150, 200, 400 ohms and in unconnected state. The load resistor of 200 ohms can be recommended for optimal performance by the results of conducted research.Low speed is the disadvantage of ozone sensor based solid electrolyte, especially when it is a long time not under the influence of ozone. Time to enter the normal mode sensor is increased in proportion to the growth of concentration of ozone. To bring the sensor to working condition when the rate of increase of the signal is maximum and constant, the required time for pre-ozonation is 25 - 30 minutes.Wider dynamic measurement range is unconditional advantage of ozone sensor based liquid electrolyte. During tests the maximum ozone concentration was set at 64 mg/m3, that was determined on power of the used ozone generator, and this not the maximum value of the measuring range.The research results showed that for compact portable indicator/meter of concentration of ozone with a range of measurements up to 10 mg/m3 more appropriate to use ozone sensor, based on solid electrolyte. Ozone sensor based on solid electrolyte has almost four times higher sensitivity, nonlinearity error lower on 4% and smaller temperature dependence, than ozone sensor based on liquid electrolyte.