Thick-Film Underground Sensors

The book covers the work on the design, fabrication of screen printed sensor arrays for deployment underground to monitor soil quality as a result of monitoring specific water parameters infiltrating the soil. Those parameters involved pH, dissolved oxygen levels, temperature and conductivity. The pH sensor is based on a potentiometric cell with a silver/silver chloride reference electrode and a ruthenium (II) oxide Ion-Selective-Electrode. The conventional Clark cell was used for the design of the dissolved oxygen sensor while the temperature sensor was based on a platinum resistance thermometer. A novel conductivity sensor was designed based on the four electrode method but instead six electrodes were used. The instrumentation for the proper operation of the sensor with relative flexibility was designed and tested. All the sensors were fabricated using Thick-Film Technology and they were printed on the same sensor array to minimise cost and size. While some of the sensors described in the book pre-existed, the application of the sensor array in soil and the techniques used to overcome the challenges are novel and provide a significant improvement in this research area.