Pd-Sensitized In 2 Se 3 Films Boost Low-Concentration H 2 Detection

Hydrogen (H 2 ) detection at room temperature (RT) remains a challenge for conventional chemiresistive sensors. Herein, we report the synthesis and integration of Pd-sensitized In 2 Se 3 (Pd-In 2 Se 3 ) films for H 2 sensors by using chemical vapor deposition and atomic layer deposition. The pristine In 2 Se 3 films exhibit a high response to NO 2 and are insensitive to H 2 . After sensitization with Pd catalysts, the Pd-In 2 Se 3 sensor becomes very sensitive to sub-ppm H 2 with fast response and recovery. To our best knowledge, this is among the limited number of studies that demonstrate the feasibility of using In 2 Se 3 materials to construct sensors for low-concentration H 2 detection at RT. Density functional theory calculations reveal that the Pd nanoparticles play a crucial role in the sensing reactions. This work sheds new light on the fabrication and integration of selenide films in high-performance sensors and also contributes to the fundamental understanding of the sensitization mechanism of catalysts in sensors.