Comprehensive Study of Hydrogen Gas Sensing Performance of an Amorphous In-Al-Zn-O (a-IAZO) Thin Film Synthesized With Pd Nanoparticles

A novel hydrogen (H2) sensor produced by the combination of an amorphous indium-aluminum-zinc-oxide (a-IAZO) thin film and palladium (Pd) nanoparticles (NPs) is demonstrated and studied herein. Elemental and morphological analyses are employed to investigate the designed device structure. The use of Pd NPs effectively increase the specific surface area, spillover effect, and catalytic activity which substantially enhances the related H2 gas sensing performance. Excellent hydrogen sensing properties, including an ultrahigh sensing response of 9.6 \times 105 accompanied by a short recovery time of 10 s under 1% H2/air gas and a lower sensing concentration of 1 ppm H2/air at 250 °C are obtained. Also, the produced device shows excellent selectivity and long-term stability in relation to H2 gas. The studied Pd NP/a-IAZO sensor also reveals merits including a simple device structure and relatively easy production process.