Hydrogen detecting characteristics of a palladium nanoparticle/indium gallium oxide based sensor

An investigation and analysis have been conducted on a newly developed chemiresistive-type sensor to detect hydrogen gas. The studied senor is synthesized with an indium gallium oxide (IGO) thin film formed by RF magnetron sputtering and palladium (Pd) nanoparticles (NPs) deposited by vacuum thermal evaporation. The utilize of Pd NPs can significantly improve the sensing response and sensing speed for hydrogen gas. Energy-dispersive X-ray spectroscopy (EDS), atomic force microscopy (AFM), high-resolution scanning electron microscopy (HRSEM), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS) are employed for the analyses of the relevant structure, element, and composition properties. The sensing mechanism for hydrogen gas is elucidated in this work. In this experiment, the studied Pd NP/IGO sensor exhibits an ultra high sensing response SR of 1.39×107 under 1% H2/air gas at 300°C.. The studied sensor can be operated at room temperature with a significant SR of 304.3. Besides, the studied sensor shows good repetitive operation performance. Hence, the studied Pd NP/IGO structure offers a great potential for the development of hydrogen sensing applications with outstanding performance.