Mesoporous WS₂/MoO₃ Hybrids for High-Performance Trace Ammonia Detection.

Area of Science:

• Materials Science
• Nanotechnology
• Chemical Sensing

Background:

• Developing sensitive and selective gas sensors is crucial for environmental monitoring and industrial safety.
• Trace ammonia (NH₃) detection is important for various applications, including food spoilage and industrial emissions.
• Existing sensors often require elevated temperatures, increasing power consumption and limiting practical use.

Purpose of the Study:

• To synthesize mesoporous WS₂/MoO₃ hybrids for high-performance trace ammonia gas detection.
• To investigate the synergistic effects of WS₂ and MoO₃ in a hybrid nanostructure for gas sensing.
• To evaluate the sensing performance of the WS₂/MoO₃ hybrids at room temperature.

Main Methods:

• Facile two-step, additive-free hydrothermal synthesis of WS₂/MoO₃ hybrids.
• Fabrication of gas sensors using the synthesized WS₂/MoO₃ materials.
• Performance testing of sensors for trace ammonia detection at room temperature (22 ± 3 °C).

Main Results:

• The optimal WS₂/MoO₃ sensor demonstrated a significantly improved response (31.58% within 57 s) to 3 ppm NH₃ compared to pure WS₂ and MoO₃.
• Achieved a low detection limit of 9.0 ppb for NH₃ with good reversibility, selectivity, and long-term stability.
• Superior sensing performance attributed to WS₂/MoO₃ heterojunctions and large specific surface area.

Conclusions:

• Mesoporous WS₂/MoO₃ hybrids exhibit excellent performance for trace NH₃ detection at room temperature.
• The synergetic effect between WS₂ and MoO₃ enhances carrier modulation and sorption kinetics.
• These heterostructure nanomaterials show potential for low-power, high-sensitivity gas sensors.