Resistive nanostructured W₁₈O₄₉ gas sensors: an overview

Area of Science:

• Materials Science
• Chemical Engineering
• Sensor Technology

Background:

• Resistive gas sensors using semiconducting metal oxides are crucial for safety.
• W18O49 (WO2.72), a tungsten oxide, offers abundant oxygen vacancies beneficial for gas adsorption and sensing.
• High-performance gas sensors are feasible through rational design of W18O49-based materials.

Purpose of the Study:

• To review the gas-sensing properties of pristine, doped, decorated, and composite W18O49.
• To provide an in-depth understanding of the sensing mechanisms of W18O49-based toxic gas sensors.

Main Methods:

• Fabrication and characterization of W18O49-based gas sensors.
• Investigation of gas-sensing performance using various strategies: morphology engineering, doping, decoration, and composite formation.
• Analysis of sensing mechanisms based on oxygen vacancies and surface reactions.

Main Results:

• W18O49 exhibits excellent electrical and sensing properties for toxic gas detection.
• Strategies like doping, decoration, and composite formation significantly enhance W18O49 gas sensor performance.
• The presence of oxygen vacancies in W18O49 is key to its gas adsorption and sensing capabilities.

Conclusions:

• Rational design of W18O49-based materials is feasible for high-performance gas sensors.
• W18O49 is a promising material for developing sensitive and inexpensive toxic gas detection systems.
• Understanding the sensing mechanism is vital for optimizing W18O49 gas sensor efficacy.