Surface and interface electronic properties of tin oxide

Abstract

Solid-state gas sensors transduce a chemical quantity, such as a gas concentration, into an electric signal. Metal-oxide semiconductors are the most common inorganicmaterials used in chemical sensing of gases and vapors. They play a major role inindustrial applications such as automotive, aerospace, and food, as well as medicaland indoor detection of toxic gases produced by incomplete combustion of heatingsystems. In particular, polycrystalline SnO2 is an attractive material due to its highsensing response to reducing gases, long-term stability, robustness, and low cost. Theexact details of the mechanisms that cause a gas response are still controversial, butit is widely accepted that trapping of electrons at adsorbed molecules and band bendinginduced by these charged molecules are responsible for a change in conductivity.