Study on Polarization Parameters of Micro Dissolved Oxygen Sensor

Based on the electrochemistry reaction mechanism, we firstly studied the reaction rates of cathode and anode, respectively. Then mathematical relationship between the reaction rates of cathode and anode under stable polarization was established. The optimum effective superficial area of the anode contacted with electrolyte was verified, which improved the detection accuracy of PPB level dissolved oxygen. After that, the relationship between polarization voltage E and two time parameters (t and t’, which are working time of the sensor, and the time taken when the dissolved oxygen concentration on both sides of the oxygen permeable membrane is balanced, respectively.) was obtained. It is confirmed that the two electrode systems existed stable working time period. Our experiments proved that the micro dissolved oxygen sensor works stably and reliably during this period of time.