Hydrogen gas sensing performance of p-type copper and titanium mixed oxides: influence of the elemental composition and the annealing temperature

In this work, mixtures of copper and titanium oxides (CuTiOx) thin films are proposed as p-type hydrogen sensing material. After the deposition by magnetron sputtering, thin films were annealed at three temperatures, up to 300 °C. The influence of post-process modification on morphology and microstructure and the effect of various ratio of copper oxides to titanium oxides was investigated. It was found that for CuTiOx exhibited an improved response to hydrogen in comparison to copper oxides or titanium oxides. The highest sensor responses (over 11) were obtained after annealing at 300 °C for thin film. To create a gas sensing mechanism, the interaction of hydrogen with the surface was investigated. Hydrogen reduces copper oxides and titanium oxides to Cu 2 O and Ti 2 O 3 . The sensing mechanism of CuTiOx is influenced by the adsorption of oxygen and reaction with hydrogen and also by the reduction of the sensing material. • Mixed copper and titanium oxides thin films are p-type hydrogen sensing material. • CuTiOx exhibited an improved response in comparison to Cu x O or TiO x thin films. • Oxide with 56 at. % of Cu exhibited the highest sensor response. • The optimal working temperature were investigated in the range from 200 to 300 °C. • After 3 min of interaction with H 2 sensor response for CuTiOx exceed 7.