Engineering Synergistic Pd-Ni Co-Modified System for Highly Efficient Hydrogen Sensing

Area of Science:

• Materials Science
• Chemical Engineering
• Sensor Technology

Background:

• Hydrogen sensors are crucial for safety in hydrogen production, storage, and transport.
• Palladium-based sensors offer good hydrogen selectivity but suffer from Pd oxidation and agglomeration, degrading performance.
• Developing sensors with low operating temperatures, high sensitivity, and selectivity remains a key challenge.

Purpose of the Study:

• To develop a novel bimetallic sensor using palladium-nickel oxide (Pd-NiO) co-modified WO3 nanospheres.
• To enhance hydrogen sensing performance, particularly at low operating temperatures.
• To investigate the synergistic effects of NiO doping on Pd-WO3 sensor characteristics.

Main Methods:

• Synthesis of Pd-NiO/WO3 nanospheres via a bimetallic modulation strategy.
• Characterization of sensor performance including response, selectivity, and stability at 160 °C.
• Mechanistic studies involving oxygen adsorption and Pd oxidation suppression.
• Machine learning-assisted gas discrimination for enhanced selectivity.

Main Results:

• The Pd-NiO/WO3 sensor demonstrated a high response (25) to 50 ppm H2 at 160 °C, significantly outperforming Pd-WO3.
• Achieved fast response-recovery times, excellent hydrogen selectivity, and good long-term stability.
• NiO doping effectively suppressed Pd oxidation and enhanced catalytic activity.
• Machine learning achieved 95.8% classification accuracy for gas discrimination.

Conclusions:

• The bimetallic Pd-NiO/WO3 nanosphere strategy offers synergistic effects for superior hydrogen sensing performance.
• The developed sensor shows practical applicability, reliably detecting hydrogen from water-splitting devices.
• This approach provides an effective route for engineering advanced synergistic co-modified systems for high-performance hydrogen sensing.