Ultra-Low Loading Single-Atom Pt-Decorated SnO₂ for High-Performance MEMS Hydrogen Sensor.

Area of Science:

• Materials Science
• Chemical Engineering
• Sensor Technology

Background:

• Real-time hydrogen (H₂) monitoring is crucial for the new energy sector.
• Developing high-response, low-cost H₂ sensors remains a significant challenge.

Purpose of the Study:

• To develop ultra-low content single-atom platinum (Pt)-loaded tin dioxide (SnO₂) sensors for enhanced H₂ detection.
• To investigate the performance and sensing mechanisms of these novel H₂ sensors.

Main Methods:

• Fabrication of SnO₂/MEMS H₂ sensors using an extended two-step annealing method.
• Loading ultra-low content (0.07 wt%) single-atom Pt onto SnO₂.
• Characterization of sensor performance, including response, operating temperature, response time, and limit of detection.

Main Results:

• The single-atom Pt-loaded SnO₂ sensor achieved ppb-level H₂ sensing with low power consumption.
• Optimal performance at 201 °C: response of 55.0 to 100 ppm H₂ (9.17x pure SnO₂).
• Reduced optimal operating temperature by ~30 °C and increased response by 45.0 compared to traditional Pt impregnation.

Conclusions:

• Single-atom Pt significantly enhances H₂ sensing performance compared to nanoparticle Pt.
• Enhanced active oxygen content and surface oxidation activity are key mechanisms.
• The developed sensor shows great potential for real-time H₂ monitoring in the new energy era.