Polar vapour detector based on thermal modulation of contact potential

Abstract

A sensitive, variable-temperature contact-potential device based on the Kelvin-Zisman method was constructed. Its use as a detector of polar vapours was demonstrated. Thermal pulsing of one plate of the apparatus results in a cycling contact potential. The thermal pulsing also aids in the removal of adsorbed molecules, thus increasing the rate of detector response. The sensitivity of the detector is adjustable by change of the base temperature. Various uses of the detector are illustrated by examples, including one demonstrating the sensitivity of gold sensors to hydrazines.