A smart H2 sensor array of QCMs coated with PdNi alloy of various thicknesses

This paper describes some of our results in developing high performance hydrogen gas sensors using piezoelectric devices (i.e., Quartz Crystal Microbalances (QCMs) and Thin Film Resonators (TFRs)) coated with a PdNi (90/10) alloy. A sensor array has been built by coating quartz crystals with various PdNi thicknesses and tested via exposure to H₂ in N₂ in the concentration range from 20 to 500 ppm. The performance of the sensor array has been also characterized in the presence of various potential interference gases and vapors, such as carbon dioxide, nitrous oxide, water, toluene, acetone, acetonitrile, hexane, methyl isobutylketone, methylene chloride, and ethanol. Using the unique chemistry of Pd-H₂ system, we have developed an relatively straightforward method to compensate for contributions from the mentioned potential interference gases