Wide range hydrogen sensing behavior of a silver delafossite: Performance towards long term stability, repeatability and selectivity

Abstract Wide range H2 sensing behavior and the long term performance of thick films of AgInO2 delafossite, composed of hexagonal nanoplates, is presented. The material responds from 1 ppm to 10,000 ppm of H2 at the operating temperature of 360 °C at different humidity levels. The material exhibits a high degree of selectivity and repeatability without any significant drift in the baseline. AgInO2 exhibits oxygen non-stoichiometry. Both chemisorbed and lattice oxygen of AgInO2 participate in gas sensing. Presence of trace levels of metallic (Ag) or oxide (In2O3) impurities degrades its sensitivity and selectivity towards hydrogen.