Cr-inserted TiO2 thin films for chemical gas sensors

Abstract Cr–Ti oxide thin films were prepared by rf sputtering of Cr-inserted Ti targets. The roles played by Cr content and thermal treatments on both the structure and the electrical conductivity of thin films were investigated. Selected series of samples were tested as sensors for different gases like carbon monoxide and ethanol. In both the cases, samples exhibiting the best sensing performances were determined and possible correlations between structure and electrical properties were evidenced.

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