Materials for solid-state gas sensors

The major problems in the development of inorganic gas-sensor materials are discussed. The general principle of semiconductor gas sensors is considered, and the band-structure parameters sensitive to the gas-phase composition are determined. Ways of improving sensor selectivity are examined. The composition, microstructure, and gas sensitivity of nanocrystalline SnO2 and ZnO are investigated. The dopant content and grain size of Ni-doped SnO2 are optimized for H2S detection. The prospects of employing systems of two or more nanocrystalline oxides (nanocomposites) for gas detection are discussed.