Investigation of the fabrication parameters of thick film titanium oxide-PVC pH electrodes using experimental designs

This paper describes a study into the development of an optimum fabrication process for the batch production of thick film titanium oxide-PVC pH electrodes. Multifactorial experimental plans are used to explore the effect of fabrication parameters on the average sensitivity of sensors and their batch variability. Analysis of the results indicates that a number of the factors have a small effect on the sensitivity. Factors of particular importance are identified and TiO2 in a PVC binder is examined in detail. The optimal values for these fabrication values are identified and examined. Mechanisms for the experimentally observed sub-Nernstian responses and immersion-time variations in sensor behaviour are discussed.