Improved hydrogen sensing behaviour in ion-irradiated Pd-Au alloy thin films

Abstract Present work reports a significant improvement in the hydrogen sensing characteristics of Pd-Au thin film by ion irradiation. The Pd-Au alloy thin film was synthesized by DC magnetron sputtering. The deposited film was irradiated by 500 keV Xe2+ ion at a fluence of 1 × 1016 ions/cm2. The characterizations of the pristine and irradiated samples were performed by XRD, AFM and TEM. The hydrogen sensing characteristics of the pristine and irradiated samples was carried out by electrical resistance measurements using 2% H2 concentration at 250 °C. The alloy film does not delaminate in hydrogen loading/deloading cycles. The improvement in sensing characteristics is attributed to ion irradiation induced defects which facilitate the rate of hydrogen absorption in the films.