Characterization of New Structural Ion Sensor using Electrochemical Impedance Method

We developed a new structural ion sensor for measuring sodium ions without using a reference electrode. The ion sensor, which is all solid state, has a structure of double electrodes inside the sodium ion sensitive membrane. The ion sensitivity of the sensor was 45 mV/decade in the range of 10-1 to 10-4 mol/l. To investigate the response mechanism of the potential between two electrodes, the impedance characteristic was measured using the electrochemical impedance method. The impedance of the ion sensitive membrane changed by changing the sodium ion concentration in solution. These results suggest a correlation between the membrane potential and the membrane impedance. In conclusion, ions in the ion sensitive membrane result in the potential gradient of the ion sensitive membrane