Selective hydrogen gas sensor using CuFe ₂ O ₄ nanoparticle based thin film

Hydrogen gas sensors based on CuFe ₂ O ₄ nanoparticle thin films are presented in this work. Each gas sensor was prepared by depositing CuFe ₂ O ₄ thin film on a glass substrate by dc sputtering inside a high vacuum chamber. Argon inert gas was used to sputter the material from a composite sputtering target. Interdigitated metal electrodes were deposited on top of the thin films by thermal evaporation and shadow masking. The produced sensors were tested against hydrogen, hydrogen sulfide, and ethylene gases where they were found to be selective for hydrogen. The sensitivity of the produced sensors was maximum for hydrogen gas at 50 °C. In addition, the produced sensors exhibit linear response signal for hydrogen gas with concentrations up to 5%. Those sensors have potential to be used for industrial applications because of their low power requirement, functionality at low temperatures, and low production cost.