Temperature dependent dual functional SnO₂ sensor for Cl₂ and NO₂.

Area of Science:

• Materials Science
• Chemical Sensors
• Nanotechnology

Background:

• Monitoring toxic gases like Cl2 and NO2 is critical in industrial and living environments.
• Current multi-gas monitoring often requires numerous sensors or frequent replacements, increasing costs and energy consumption.
• Development of single sensors capable of detecting multiple gases is highly desirable.

Purpose of the Study:

• To develop a multifunctional gas sensor capable of detecting both Cl2 and NO2.
• To investigate the sensing performance of SnO2 thin films for dual gas detection.
• To explore the influence of working temperature on the sensor's selectivity and performance.

Main Methods:

• Synthesis of SnO2 thin films from 4-6 nm nanoparticles using a hydrothermal method.
• Fabrication of a gas sensor utilizing the synthesized SnO2 thin film.
• Testing the sensor's response to Cl2 and NO2 at different working temperatures (50°C and 90°C).

Main Results:

• The SnO2 thin film sensor demonstrated dual functionality, detecting both Cl2 and NO2.
• At 50°C, the sensor achieved a high response of 1386 to 5 ppm Cl2.
• At 90°C, the sensor exhibited excellent performance for 5 ppm NO2, with a response of 417 and a recovery time of 15 s.
• The sensor showed good reproducibility, long-term stability, and moisture resistance.

Conclusions:

• The developed SnO2 thin film sensor effectively achieves dual sensing of Cl2 and NO2 by adjusting working temperature.
• This multifunctional sensor offers a promising solution for efficient and cost-effective multi-gas monitoring.
• The findings encourage the development of novel multifunctional sensing materials and further exploration of their sensing mechanisms.