Cl− and H+ sensing devices for water quality monitoring system

In this study, the water quality monitoring system with wireless remote control platform was investigated. And the sensing properties of the Cl^- sensing device and the pH sensor were discussed. The pH sensing membrane, ruthenium dioxide (RuO₂) was deposited on the silicon substrate by radio frequency (R. F.) sputtering system. The chlorine ion selective membrane was prepared on the pH sensing membrane thin film by spin coating method. Furthermore, the response time of the Cl^- sensing device and pH sensing device were less than 30 s and 10 s, respectively. Moreover, the lifetime of the Cl^- sensing device was immersed in 7.3 ppm of Cl^- concentration in NaClO solution at least 3 days. The lifetime of the pH sensing device was immersed in pH 7 buffer solution at least 15 days. According to the experimental results, Cl^- sensing device and pH sensing device can be applied to water quality monitoring system for real-time measurement and long-term measurement.