Thin films of porphyrin-chalcogenide nanocomposite for methane sensing at room temperature

Abstract

Methane is one of the components of natural gas and has multiple applications. It is an odorless gas, flammable and combustible in the presence of oxygen. Its lower explosion limit (LEL) is 5.0 vol.%, which corresponds to 50 000 ppm, while the upper explosion limit (UEL) is 15 vol% [1]. The classical and versatile SnO2 gas sensing material was initially developed by researchers from Japan, several decades ago [2]. The gas sensing material is generally deposited onto planar interdigitated electrodes (IDEs), or onto some functionally equivalent structure, like coils or meshes. The back side of the IDE is provided, in most cases, with a continuous electrode for heating, to allow setting the working temperature of the sensor for the gas to be detected.