Thick film screen printed environmental and chemical sensor array reference electrodes suitable for subterranean and subaqueous deployments

Purpose - Thick film environmental and chemical sensor arrays designed for deployment in both subterranean and submerged aqueous applications are reported.Design/methodology/approach - Various choices of materials for reference electrodes employed in these different applications have been evaluated and the responses of the different sensor types are compared and discussed. Findings - Results indicate that the choice of binder materials is critical to the production of sensors capable of medium term deployment (e.g. several days) as the binders not only affect the tradeoff between hydration time and drift but also have a significant bearing on device sensitivity and stability. Sensor calibration is shown to remain an issue with long term deployments (e.g. several weeks) but this can be ameliorated in the medium term with the use of novel device fabrication and packaging techniques.Originality/value – The reported results indicates that is possible through careful choice of materials and fabrication methods to achieve near stable thick film reference electrodes that are suitable for use in solid state chemical sensors in variety of different application areas