The use of thin silver films for the detection of low concentrations of hydrogen sulphide

This work describes the facile fabrication of a sensor for the visual detection of hydrogen sulphide at concentrations of ≥0.1 ppm. Colloidal silver films were prepared on PVC by a dip-coating method which, on exposure to hydrogen sulphide, underwent a colour change from yellow/grey to black. The rate of change was considerably faster than for films prepared by vacuum deposition. A visual change of the colloidal silver film was observed for hydrogen sulphide at 1 ppm within 10 min and at 0.1 ppm in 60 min.