Ultrasensitive hydrogen sensor based on Pt-decorated WO₃ nanorods prepared by glancing-angle dc magnetron sputtering

Area of Science:

• Materials Science
• Nanotechnology
• Chemical Sensing

Background:

• Tungsten trioxide (WO3) nanostructures are promising semiconductor materials for gas sensing.
• Enhancing the sensitivity and selectivity of WO3-based sensors is crucial for practical applications.

Purpose of the Study:

• To develop an ultrasensitive hydrogen (H2) sensor.
• To investigate the effect of platinum (Pt) nanoparticle decoration on WO3 nanorod gas-sensing performance.
• To optimize Pt decoration time for maximum H2 response.

Main Methods:

• Fabrication of WO3 nanorods using dc magnetron sputtering with glancing angle deposition (GLAD).
• Decoration of WO3 nanorods with Pt nanoparticles via normal dc sputtering with varying deposition times.
• Characterization using X-ray diffraction, field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, and photoelectron spectroscopy.
• Gas sensing performance evaluation for H2 detection at various concentrations and temperatures.

Main Results:

• Pt decoration significantly impacts H2 sensing performance of WO3 nanorods.
• Optimal H2 response was achieved with Pt deposition time up to 10 s.
• The sensor demonstrated an ultrahigh H2 response (1530 to 214,000) for 150-3000 ppm H2 at 200 °C.
• Performance is attributed to fine Pt nanoparticle dispersion and large effective surface area.

Conclusions:

• Pt-decorated WO3 nanorods offer excellent H2-sensing capabilities.
• The sensor exhibits high sensitivity and rapid response, suitable for H2 detection.
• Optimized Pt nanoparticle decoration is key to achieving superior gas-sensing properties.