Specific palladium and platinum doping for SnO2-based thin film sensor arrays

doi:10.1016/0925-4005(93)85346-C

Sensors and Actuators B: Chemical

Volume 13, Issues 1–3, May 1993, Pages 143-147

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Abstract

Undoped, Pd- and Pt-doped SnO₂-based thin film chemical sensors have been developed. The distribution of metallic dopant atoms and ions at the surface and at bulk positions of the SnO₂ lattice was adjusted during the preparation and subsequent temperature treatment at constant oxygen partial pressure. The sensitivities and selectivities of these SnO₂ thin film conductance sensors to detect small concentrations of NO₂, CH₄, CO and H₂ in air were characterized. The different contributions from contacts, surface, bulk and grain boundaries to the sensor response were separated with two-, three- and four-point d.c. and a.c. measurements using different electrode configurations. Finally, we evaluated responses from sensor arrays to CO/NO₂ and CO/CH₄ mixtures with PCA (principal component analysis), PLS (partial least squares) and PCR (principal component regression) to analyse these mixtures quantitatively.

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Specific palladium and platinum doping for SnO2-based thin film sensor arrays

Abstract

Sensors and Actuators B

Sensors and Actuators

Sensors and Actuators B

Sensors and Actuators B

Vacuum

Fresenius Z. Anal. Chem.

Specific palladium and platinum doping for SnO₂-based thin film sensor arrays