Gas sensors based on plasma-electrochemically oxidized titanium foils

Abstract

We have developed a preparation technique to form graphite/TiO2/Ti and platinum-graphite/TiO2/Ti solid-state sensors. It is based on plasma electrolytic oxidation (PEO) of titanium foils, whereby a porous titanium oxide layer is formed with well-defined phase composition and a reproducible microstructure. A printing method is used to deposit graphite or catalytically active graphite-platinum electrodes. Our design enables the application of a variety of different detection principles such as calorimetry, impedances and amperometry. This study reports results for H2, H2O, and CO sensing at room temperature with the most appropriate detection principle, electrode composition and titanium oxide microstructure.