Research On Metal Oxide PH Sensors

Metal oxide pH sensor has the advantages of fast response,good stability and high reliability,and has certain applications in water quality monitoring,biomedicine,food monitoring and other fields.The Interdigitated electrodes has the advantages of small size and low manufacturing cost.In the field of electrochemical detection,the metal oxide pH sensor based on the interdigitated electrodes has important research significance.In this paper,the metal oxide pH sensor with interdigitated electrodes is studied deeply.the main contents are as follows:（1）Software is used to build different interdigitated electrodes models for simulation research,change the parameters of the interdigitated electrodes（width,spacing）,analyze and compare its electric field intensity,calculate the impedance and impedance variation of the sensor based on the interdigitated electrodes in aqueous solution with different conductivity,and analyze and optimize it.The optimal interdigitated electrodes size was obtained as follows:The length of the interdigitated electrodes is 4mm,the width of the interdigitated electrodes is0.5mm,and the spacing is 0.5mm.This work provides a theoretical reference for the design of practical sensors.（2）The optimum parameters of the interdigitated electrodes are prepared by screen printing technology,and the material of the interdigitated electrodes are optimized.The interdigitated electrodes are modified with pH-sensitive materials of different components,The proportion of epoxy resin is fixed at 40%,and the ratio of RuO₂ and toner includes three kinds:2:1,3:2 and 1:1,The sensitivity,stability,reproducibility and hysteresis effects of the sensor are investigated by using the unmodified interdigitated electrodes and the carbon powder modified interdigitated electrodes as the control group.The results showed that the pH sensor with the highest content of ruthenium oxide had the best sensitivity,and the sensor had good stability,reproducibility and low hysteresis effect.