Resistivity Sensors of Metal Oxides with Metal Nanoparticles as Catalysts
The metal oxide resistivity sensors are the most common sensors for reducing and oxidizing gases, due to their low cost, easiness of preparation and signal processing. The sensing properties of a metal oxide film depend on the surface roughness, porosity, crystallinity and some other factors, which differentiate for each preparation method. Moreover, the addition of noble nanoparticles on the surface of the films, improves the sensing properties of the films. In this work two different techniques were used to prepare thin films of metal oxides doped with noble metals and their sensing properties for different reducing gases were investigated. Namely we used the (a) PLD technique to prepare thin films of Cu x O (1 < x < 2) doped with Au and testing them as CO and CH4 sensors. (b) Sol-gel technique to prepare ZnO thin films doped with Au as H2 and acetone sensors. All the films are characterized. A significant response to several concentrations of the analytes was demonstrated for all the films at temperatures lower than 200 ∘C.
KeywordsNoble Metal Pulse Laser Deposition Zinc Acetate Dihydrate Metal Oxide Film Resistivity Sensor
The authors would like to acknowledge the financial support from the Greek General Secretariat for Research and Technology and the European Commission, through the European Social Fund for Regional Development, NHRF 2007–2013 action ‘Development of Research Centres – KPH\(\Pi\) I\(\Sigma\)’, project 447963 ‘New Multifunctional Nanostructured Materials and Devices–POLYNANO’.
- 10.Henrich VE, Cox PA (1994) The surface science of metal oxides. Cambridge University Press, CambridgeGoogle Scholar