Polystyrene-coated Interdigitated Microelectrode Array to Detect Free Chlorine towards IoT Applications.

We apply interdigitated microelectrode array (IDA) sensors for water quality monitoring. IDA sensors with an ion-sensitive coating show higher sensitivity of about 600 mV with the hypochlorite ion concentration increasing from 0 to 10 ppm more than the traditional sensing method. The response mechanism and selectivity have been studied. Several material components that affect the sensing process were explored. Coupling agents and plasticizer were introduced into the coating material to improve the coating material quality and its adhesion to the electrodes. The stability/repeatability and linearity have been significantly improved.