Pd-Decorated PdO Hollow Shells: A H₂-Sensing System in Which Catalyst Nanoparticle and Semiconductor Support are...

Area of Science:

• Materials Science
• Nanotechnology
• Chemical Engineering

Background:

• Developing high-performance hydrogen sensors with long-term stability is challenging.
• Traditional sensors like Pd/TiO2 and Pd/ZnO face limitations in stability and nanoparticle management.
• A novel approach is needed to improve sensor durability and performance.

Purpose of the Study:

• To develop a simple and effective strategy for fabricating high-performance hydrogen sensors.
• To investigate the hydrogen-sensing properties of Pd-decorated PdO hollow shells (Pd/PdO HSs).
• To explore the unique interconvertible nature and reactivation ability of the Pd/PdO system.

Main Methods:

• Fabrication of Pd-decorated PdO hollow shells (Pd/PdO HSs) via a one-step NaBH4 treatment.
• Partial reduction of PdO to Pd, leading to controlled decoration of Pd nanoparticles (Pd NPs) on the PdO support.
• Investigation of the physical embedding of Pd NPs within the PdO support to prevent agglomeration and enhance electron transfer.

Main Results:

• Pd/PdO HSs exhibit excellent hydrogen-sensing performance with a detection limit below 1 ppm.
• Achieved rapid response and recovery times of 5 s and 32 s, respectively, at room temperature for 1% H2.
• Demonstrated repeatable reactivation of sensing performance by reoxidizing PdO HSs, extending sensor lifetime.

Conclusions:

• The presented strategy offers a convenient, time-saving method for fabricating stable hydrogen sensors without surface prefunctionalization.
• The interconvertible and self-repairing nature of the Pd/PdO system provides a novel pathway for enhancing sensor longevity.
• Pd/PdO HSs represent a promising material for advanced, long-lasting hydrogen sensing applications.